I opened the latest version of the Silverlight dll Telerik.Windows.Themes.Windows8.dll and looked at the resource RadRadioButtonStyle. In the decompiled output I find things like example 1 below. Note the line in bold and Italic (VisibleVisible). This will obviously not compile when I try to use it. Another problem is that it generates <Grid.VisualStateGroups> instead of <VisualStateManager.VisualStateGroups>. This does not compile either.