the window, if moved or resized horizontally, moves or resizes to the opposite direction in very strange mode.
[A simple project for demostration of the those behaviours attached to this message.]
There is not possibility to add project rar file, so I add the sources here.
App.xaml
<Application x:Class="MDIWindows.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
StartupUri="Window1.xaml">
<Application.Resources>
</Application.Resources>
</Application>
Window1
<Window x:Class="MDIWindows.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="198" Width="300">
<StackPanel>
<Button Content="Open" Click="OnOpenClick" Height="40" />
<Button Content="BringToFront" Click="OnBringToFrontClick" Height="40" />
</StackPanel>
</Window>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Telerik.Windows.Controls;
using WpfApplication1;
namespace MDIWindows
{
 /// <summary>
 /// Interaction logic for Window1.xaml
 /// </summary>
 public partial class Window1 : Window
 {
  Example window;
  public Window1( )
  {
   InitializeComponent();
  }
  private void OnOpenClick( object sender, RoutedEventArgs e )
  {
   if( window == null )
   {
    window = new Example();
    window.Width = 200;
    window.Height = 200;
    window.Owner = this;
   }
   window.Show();
  }
  private void OnBringToFrontClick( object sender, RoutedEventArgs e )
  {
   if( window == null )
    window.BringToFront();
  }
 }
}
Example
<telerik:RadWindow x:Class="WpfApplication1.Example"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:telerik="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Navigation"
x:Name="window" Header="ABC" WindowStartupLocation="CenterScreen" FlowDirection="RightToLeft" Width="400" Height="244">
</telerik:RadWindow>
using System;
using System.Windows;
using System.Windows.Media;
using Telerik.Windows.Controls;
using WindowStartupLocation = System.Windows.WindowStartupLocation;
using WindowState = System.Windows.WindowState;
namespace WpfApplication1
{
 public partial class Example : Telerik.Windows.Controls.RadWindow
 {
  public Example( )
  {
   InitializeComponent();
  }
 }
}
