I think the first thing to try is to uninstall and reinstall Generations. Does that make any difference?
Try rebuilding the index -- Option menu, Indexing, Rebuild Index.
Can you test a copy of your family file on another computer?
Please create a small test family file to see if the problem occurs in there. If that works ok, I suggest that you revert to your last good backup. I recommend that you create several copies of your backups before you open them.