I have been noticing that on your RadForm there is a problem with how you get your GetDCEx. To keep it short I'll give you a short piece of code that can help you.
if
(msg.Msg != (int)WindowMessages.WM_NCPAINT)
{
return GetWindowDC(msg.HWnd);
}
int flags = (int)(DCX.DCX_CACHE | DCX.DCX_CLIPSIBLINGS
|
DCX.DCX_WINDOW );
IntPtr zero = IntPtr.Zero;
if (msg.WParam.ToInt32() != 1)
{
flags |= (
int)DCX.DCX_INTERSECTRGN;
zero = msg.WParam;
}
return GetDCEx(msg.HWnd, zero, flags);