This is a long shot, but the next time part of the dialog window disappears, open the task manager, click on the Processes tab, then sort on the GDI Objects column. While Windows has an absolute limit of 10,000 GDI's, realize that many programs consume many hundreds of GDI objects, and it's not unusual to have more than a hundred processes running at any time. (Every icon, pointer, checkbox, window, image - everything graphic needs a GDI).
As I said, this is a long shot. I have only seen a single case of running out of GDI's and that was a programming error.
Steve Mann
MannMade Digital Video
http://www.mmdv.com
