... here is the XAML that defines the left form in the screenshot. It is now included as embedded resource and loading and displaying the form works fine. I'm going to start working on the events now.
<cTestForm Id="FrmLayoutTest" Alpha="200" BackColor="0, 74, 127, 255" BorderColor="95, 158, 160, 255" CaptionColor="0, 54, 107, 255"
TextColor="255, 215, 0, 255" Text="UI Test" TextAlignment="MIDDLE_CENTER" BarWidth="32" CaptionPosition="RIGHT"
Font="Arial_16_bold" FontSize="16" FontStyle="BOLD" Width="375" Height="250" PositionX="600" PositionY="125"
xmlns="clr-namespace:PraetorTest;assembly=PraetorTest"
xmlns:foc="clr-namespace:FoC.Praetor4UI.Controls;assembly=Praetor4UI"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<cTestForm.Controls>
<foc:cPraePanel Id="PnlCaptionPosition" Width="115" Height="145" BorderColor="95, 158, 160, 255" PositionX="5" PositionY="5"
BackColor="0, 0, 0, 0">
foc:cPraePanel.Controls
<foc:cPraeLabel Id="LblCaptionposition" BorderColor="255, 255, 255, 255" Font="Arial_10" FontSize="10" FontStyle="NORMAL"
Width="105" Height="18" PositionX="5" PositionY="5" ResizeEnable="NONE" Text="Caption Position"
TextAlignment="MIDDLE_CENTER" TextColor="255, 215, 0, 255" />
<foc:cPraeImageButton Id="BtnUp" BackColor="173, 216, 230, 255" BorderColor="255, 255, 255, 255" Height="31"
HighlightColor="255, 255, 255, 255" Image="Button_up" PositionX="41" PositionY="35"
Width="31" />
<foc:cPraeImageButton Id="BtnLeft" BackColor="173, 216, 230, 255" BorderColor="255, 255, 255, 255" Height="31"
HighlightColor="255, 255, 255, 255" Image="Button_left" PositionX="5" PositionY="71"
Width="31" />
<foc:cPraeImageButton Id="BtnRight" BackColor="173, 216, 230, 255" BorderColor="255, 255, 255, 255" Height="31"
HighlightColor="255, 255, 255, 255" Image="Button_right" MaxHeight="0" PositionX="77"
PositionY="71" Width="31" />
<foc:cPraeImageButton Id="BtnDown" BackColor="173, 216, 230, 255" BorderColor="255, 255, 255, 255" Height="31"