Tabs not drawing correctly... What am I doing wrong?

[Mike Baldini]

I am hoping that I am doing something really stupid here.

Anyway, the Initial rendering of the tabs (when the program loads) looks perfect.
Initial Rendering

But when you switch tabs, it looks like the very bottom most (or top most if the tabs locations was set to 'top') are being drawn incorrectly.
Switch Tab 1
Switch Tab 2

Can somebody explain this? This issue is of relative importance, and must be resolved before we release the final version of the program in May.

Here is the contents of the XML file for the theme.

<?xml version="1.0" encoding="utf-8"?>
<XmlTheme xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" ThemeName="RoundedTabBottom">
  <BuilderRegistrations>
    <XmlStyleBuilderRegistration>
      <BuilderData xsi:type="XmlStyleSheet" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
        <PropertySettingGroups>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="Transparent" NumFrames="4" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="">
                <Step StepType="Telerik.WinControls.ColorAnimationStep" Value="-51, 0, 0, 0" />
                <ReverseStep StepType="Telerik.WinControls.ColorAnimationStep" Value="51, 0, 0, 0" />
              </XmlAnimatedPropertySetting>
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="214, 221, 234" NumFrames="4" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="">
                <Step StepType="Telerik.WinControls.ColorAnimationStep" Value="-31, 0, 0, 0" />
                <ReverseStep StepType="Telerik.WinControls.ColorAnimationStep" Value="51, 0, 0, 0" />
              </XmlAnimatedPropertySetting>
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="Transparent" NumFrames="4" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="">
                <Step StepType="Telerik.WinControls.ColorAnimationStep" Value="-51, 0, 0, 0" />
                <ReverseStep StepType="Telerik.WinControls.ColorAnimationStep" Value="51, 0, 0, 0" />
              </XmlAnimatedPropertySetting>
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="225, 231, 239" NumFrames="4" Property="Telerik.WinControls.VisualElement.BackColor" Value="">
                <Step StepType="Telerik.WinControls.ColorAnimationStep" Value="-31, 0, 0, 0" />
                <ReverseStep StepType="Telerik.WinControls.ColorAnimationStep" Value="31, 0, 0, 0" />
              </XmlAnimatedPropertySetting>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Linear" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="1" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="0.666" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="2" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Padding" Value="0, 0, 0, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabFill" AutoUnapply="False">
                <Condition xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlAnimatedPropertySetting EndValue="199, 219, 240" NumFrames="4" Property="Telerik.WinControls.VisualElement.BackColor" Value="0, 255, 186, 91">
                <Step StepType="Telerik.WinControls.ColorAnimationStep" Value="20, 0, 0, 0" />
                <ReverseStep StepType="Telerik.WinControls.ColorAnimationStep" Value="-20, 0, 0, 0" />
              </XmlAnimatedPropertySetting>
              <XmlAnimatedPropertySetting EndValue="224, 225, 217" NumFrames="4" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="0, 234, 243, 253">
                <Step StepType="Telerik.WinControls.ColorAnimationStep" Value="36, 4, -10, -40" />
                <ReverseStep StepType="Telerik.WinControls.ColorAnimationStep" Value="-36, -4, 10, 40" />
              </XmlAnimatedPropertySetting>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
              <XmlAnimatedPropertySetting EndValue="211, 222, 227" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="0, 243, 245, 244" />
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="226, 212, 168" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="4" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Linear" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.4931271" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="0.5051546" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabFill" AutoUnapply="False">
                <Condition xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.Font" Value="Tahoma, 8.25pt" />
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="45, 94, 162" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Padding" Value="6, 3, 6, 3" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Shape" Value="Telerik.WinControls.UI.TabOffice12Shape" />
            </PropertySettings>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.UI.TabItem" AutoUnapply="False" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="180, 198, 246" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="180, 198, 246" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.109965637" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Linear" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="233, 238, 250" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="232, 239, 248" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="1" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="3" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="5, -2, 5, 5" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Shape" Value="Telerik.WinControls.RoundRectShape|2" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ZIndex" Value="6" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabBaseFill" AutoUnapply="False" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Visibility" Value="Visible" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.BoxStyle" Value="FourBorders" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.LeftColor" Value="149, 189, 231" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.BottomColor" Value="Transparent" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.RightColor" Value="149, 189, 231" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.TopColor" Value="149, 189, 231" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabItemBorder">
                <Condition xsi:type="XmlComplexCondition" BinaryOperator="OrOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="226, 231, 247" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor2" Value="156, 190, 250" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor3" Value="146, 176, 216" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor4" Value="106, 140, 200" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientStyle" Value="Solid" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabBaseBorder" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="231, 239, 249" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Solid" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabFill" AutoUnapply="False">
                <Condition xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="199, 213, 249" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Linear" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="1" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="0.666" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="180, 198, 246" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="ControlLightLight" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="2" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Visibility" Value="Visible" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabFill" AutoUnapply="False">
                <Condition xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.83" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Solid" />
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="Transparent" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="False" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="1" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Shape" Value="Telerik.WinControls.CustomShape|0,0,320,120:100,0,False,0,0,0,0,0:220,0,True,310,0,230,120,0:320,120,False,0,0,0,0,0:0,120,True,90,120,10,0,0:" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Padding" Value="0, 0, 0, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.AutoSizeMode" Value="Auto" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.StretchHorizontally" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.StretchVertically" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.PositionOffset" Value="0, 5" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="0.666" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="Transparent" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="Transparent" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="Transparent" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Visibility" Value="Hidden" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabFill" AutoUnapply="False" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Visibility" Value="Hidden" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="158, 173, 210" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientStyle" Value="Solid" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor2" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor3" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor4" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Padding" Value="0, 0, 0, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.Width" Value="1" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabItemBorder" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.ShouldPaint" Value="True" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabItemBorder" AutoUnapply="False">
                <Condition xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="191, 219, 254" />
              <XmlPropertySetting Property="Telerik.WinControls.RootRadElement.UsePaintCache" Value="False" />
            </PropertySettings>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.RootRadElement" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="158, 173, 210" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientStyle" Value="Solid" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientAngle" Value="270" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor2" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor3" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor4" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Padding" Value="0, 0, 0, 0" />
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="-20, 0, -20, 0" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabItemBorder">
                <Condition xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                  <Condition1 xsi:type="XmlComplexCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Condition1 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                      <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
                    </Condition1>
                    <Condition2 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                      <Setting Property="Telerik.WinControls.VisualElement.IsMouseDown" Value="True" />
                    </Condition2>
                  </Condition1>
                  <Condition2 xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
                  </Condition2>
                </Condition>
              </XmlClassSelector>
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.UI.TabLayoutPanel.ItemsOffset" Value="52" />
              <XmlPropertySetting Property="Telerik.WinControls.UI.TabLayoutPanel.ItemsOverlapFactor" Value="-8" />
              <XmlPropertySetting Property="Telerik.WinControls.UI.TabLayoutPanel.AllTabsEqualHeight" Value="False" />
              <XmlPropertySetting Property="Telerik.WinControls.UI.TabLayoutPanel.TabsPosition" Value="Bottom" />
            </PropertySettings>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.UI.TabLayoutPanel" AutoUnapply="False" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.5" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="RadArrowButtonFill" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="214, 231, 255" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="214, 231, 255" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="173, 199, 239" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="4" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.4536741" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="222, 235, 255" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="0.4504792" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Linear" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="ScrollButtonFill" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="146, 176, 216" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor2" Value="156, 190, 250" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor3" Value="146, 176, 216" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor4" Value="106, 140, 200" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.GradientStyle" Value="Linear" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="RepeatScrollButtonBorder" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="Navy" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="ScrollButtonArrow" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.NumberOfColors" Value="4" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientStyle" Value="Linear" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientAngle" Value="90" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.4408946" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage2" Value="0.4920128" />
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="255, 252, 240" Property="Telerik.WinControls.VisualElement.BackColor" Value="" />
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="255, 222, 170" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor2" Value="" />
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="255, 199, 64" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor3" Value="" />
              <XmlAnimatedPropertySetting StartValueIsCurrentValue="False" EndValue="255, 252, 240" Property="Telerik.WinControls.Primitives.FillPrimitive.BackColor4" Value="" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="ScrollButtonFill">
                <Condition xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
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              <XmlClassSelector ElementClass="RadArrowButtonFill" />
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          <XmlPropertySettingGroup>
            <PropertySettings>
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          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Shape" Value="(none)" />
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              <XmlClassSelector ElementClass="DropDownButtonArrowButton" />
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          <XmlPropertySettingGroup>
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              <XmlPropertySetting Property="Telerik.WinControls.Primitives.FillPrimitive.GradientPercentage" Value="0.4408946" />
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              <XmlClassSelector ElementClass="RadArrowButtonFill">
                <Condition xsi:type="XmlSimpleCondition" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
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          <XmlPropertySettingGroup>
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              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Visibility" Value="Collapsed" />
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            <Selectors>
              <XmlClassSelector ElementClass="DropDownButtonBorder" />
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          <XmlPropertySettingGroup>
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            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.BackColor" Value="179, 191, 211" />
              <XmlPropertySetting Property="Telerik.WinControls.UI.RadTabStripElement.TabsPosition" Value="Bottom" />
              <XmlPropertySetting Property="Telerik.WinControls.UI.RadTabStripElement.ItemsOffset" Value="10" />
              <XmlPropertySetting Property="Telerik.WinControls.UI.RadTabStripElement.AllTabsEqualHeight" Value="True" />
            </PropertySettings>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.UI.RadTabStripElement" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.PositionOffset" Value="0, 0" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabHeadFill" />
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          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.Font" Value="Arial, 9.75pt" />
              <XmlPropertySetting Property="Telerik.WinControls.VisualElement.ForeColor" Value="71, 71, 71" />
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              <XmlPropertySetting Property="Telerik.WinControls.RadElement.PositionOffset" Value="0, 5" />
            </PropertySettings>
            <Selectors>
              <XmlClassSelector ElementClass="TabItemText" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.Layouts.DockLayoutPanel" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.RadHostItem" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <PropertySettings>
              <XmlPropertySetting Property="Telerik.WinControls.RadElement.Margin" Value="0, 5, 0, 0" />
            </PropertySettings>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.Layouts.BoxLayout" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <Selectors>
              <XmlClassSelector ElementClass="TabStripLeftButton" />
            </Selectors>
          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <Selectors>
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          <XmlPropertySettingGroup>
            <Selectors>
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            <Selectors>
              <XmlClassSelector ElementClass="TabItem" AutoUnapply="False">
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          <XmlPropertySettingGroup>
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              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.RightColor" Value="149, 189, 231" />
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              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor3" Value="ControlDark" />
              <XmlPropertySetting Property="Telerik.WinControls.Primitives.BorderPrimitive.ForeColor4" Value="ControlDark" />
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              <XmlPropertySetting Property="Telerik.WinControls.RadElement.PositionOffset" Value="0, 5" />
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                    <Setting Property="Telerik.WinControls.VisualElement.IsMouseOver" Value="True" />
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                  <Condition2 xsi:type="XmlSimpleCondition" UnaryOperator="NotOperator" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                    <Setting Property="Telerik.WinControls.UI.RadTabStripElement.IsSelected" Value="True" />
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                </Condition>
              </XmlClassSelector>
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          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <Selectors>
              <XmlTypeSelector ElementType="Telerik.WinControls.Layouts.ImageAndTextLayoutPanel" />
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          <XmlPropertySettingGroup>
            <Selectors>
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          </XmlPropertySettingGroup>
          <XmlPropertySettingGroup>
            <Selectors>
              <XmlClassSelector ElementClass="Separator" />
            </Selectors>
          </XmlPropertySettingGroup>
        </PropertySettingGroups>
      </BuilderData>
      <StylesheetRelations>
        <RadStylesheetRelation ControlType="Telerik.WinControls.UI.RadTabStrip" ElementType="Telerik.WinControls.RootRadElement" />
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  </BuilderRegistrations>
</XmlTheme>

[Nikolay]

Hello Mike Baldini,

Thank you for the question.

The ecountered behavior comes from the fact that you have used the PositionOffset property. Instead, you should use the Padding/Margin properties. In addition, if you want your element to have one and the same value in all states, you can set it in the InitialState only. You do not need to set it in the other states. Please find attached a modified version of your theme where the issue is addressed.

I hope this helps. If you have additional questions, feel free to contact me.

Best wishes,
Nikolay
the Telerik team

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[Mike Baldini]

I adjusted the margin and put the position offset back to 0 as you suggested, but I am now getting a very weird effect.

Please see the attached picture for an example. The tab in question is on the bottom left, just underneath the 'Contact List'

[Mike Baldini]

Nevermind. The theme manager just had not picked up on the changes. I had to restart Visual Studio for the theme manager to see the changes to the file.