There's an easy way to check and see if yor theory is correct. In the CodeWarrior IDE's editor, call up the Find function by typing CTNL-F. Now, hit the escape key, which should dismiss the dialog (the same as clicking Cancel), and you should get control of the editor back.
If it is a case of the dialog being off-screen, now go to the IDE (NOT project) settings panels. That's Edit > Preferences. In the IDE Preferences panels, pick the Editor settings panel. In the Remember group, uncheck Window position and size. To be safe, also uncheck Selection position. Quit the IDE. Relaunch the IDE, and see if the problem has been corrected.
---Tom