MFC is designed to use the regular windwows settings in Desktop->Properties->Appearance. It's not really designed to support application based themes.
You can of course override every controls'/dialogs' OnPaint (defined in CWnd) and let them do something wild...
To handle themes you'd have to implement a framework that, based on some theme-info, paints in this-or-that way.
If you want to go really crazy and use non-rectangular windows its a bit trickier...see SetWindowRgn in MSDN.
/Per
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