I hate to be a pest on this subject, but I still haven't come up with the cause of the problem nor the solution. Again, I have comboboxes that pull down when I click on the handle but it does not display the text. However, if I arrow-down while it is open I can then see and select (by hitting return but not clicking) each item.
I have quite a few comboboxes (22) on the window and they are inside a groupbox. Any chance either of these instances should make a difference?