I'm in the process of adding a bunch of new .NET functionality to a (poorly 
behaved) legacy MFC application.  One of the things I'm adding is a "source 
code editor" (ala VBA): the window should minimize/restore separately from 
the main application, have its own menu/toolbar, etc.

The first approach was straight-forward enough: create the "application" as 
a Form and use it as a modeless dialog.  However, things didn't work right 
with menu keyboard accelerators and the like (Ctrl-C, Alt-X, F1), apparently 
a result of the main MFC application grabbing them.

So, the approach that I've been using for the past several weeks is to 
create my own Application in a separate thread.  See 
http://discuss.develop.com/archives/wa.exe?A2=ind0401a&L=dotnet-winforms&T=0&F=&S=&P=3005
 and  http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=193220&SiteID=1. 
This has been working reasonably well, also having to Invoke() back to the 
main thread at times is a pain.

However, I'm now seeing some crashes with very strange call stacks such as:
    System.OutOfMemoryException: Out of memory.
       at System.Drawing.Graphics.FromHdcInternal(IntPtr hdc)
       at System.Windows.Forms.PaintEventArgs.get_Graphics()
       at System.Windows.Forms.Control.PaintException(PaintEventArgs e)
       at System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs 
e, Int16 layer, Boolean disposeEventArgs)
       at System.Windows.Forms.Control.WmEraseBkgnd(Message& m)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
       at System.Windows.Forms.ContainerControl.WndProc(Message& m)
       at System.Windows.Forms.UserControl.WndProc(Message& m)
       at 
System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& 
m)
       at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, 
IntPtr wparam, IntPtr lparam)
this seems to occur when the user tries to move my "application" window 
immediately after I've Invoke()d to the main thread.  Also, I'd like a 
little bit better window management integration with the legacy MFC 
application; for example, I don't want one of its modal (error) dialogs to 
get hidden behind this editor application window.

With that extensive background; the most recent thing I've tried is to use 
this top-level Form from MFC via the CWinFormsDialog<> class.  After setting 
TopLevel=false on my Form, the form is displayed--although the results are 
quirky as I see two sets of non-client area items (close, minimize, 
maximize, etc.).  But the bigger problem is that I can't get the keyboard 
accelerators working.  I've overridden PreTranslateMessage() and tried 
calling Control.PreProcessMessage() (and the like), but it doesn't seem to 
work.

At this point, I'm trying to figure out where to go next: sticking with a 
separate .NET Application in it's own thread is fine, but I've got no idea 
what could be causing the crash above.  And even then, there are still 
glitches with getting windows "owned" correctly (and the legacy MFC 
application has it's own ideas too).

Switching to MFC for at least some of the "application" shell (although as 
absolutely little as possible in MFC!) might help, but not if I can't get 
the keyboard accelerators.  Is what I'm trying to do in MFC possible? 
supported?  If not, what are the alternatives?  My .NET UI has docking 
windows and MDI; I *really* don't want to have to do all that "shell" in 
MFC--even if the content are WinForms controls.

Thanks for any tips/advice/pointers/etc.

   Dan