Hey, bigstar,
You know windows is at the liberty of the quirks of DirectX, and I'm wondering.. Could you look into adding some backup-feature that would prevent DirectX from resizing the main window when it changes the screen resolution temporarily? I know, it probably should be its job to restore the windows to their former state, but it simply doesn't do that, and it annoys me. Heck, it even happens when ffxp is minimized.