PSE5 organizer on Windows 7 64-bit hangs on one catalog

Question

Okay, I know using PSE5 on Win7 64-bit isn't officially supported, but a lot of people seem to be having success.
I'm migrating from XP, and backed up my catalog of 17000+ pictures.  When I installed PSE5 (and 5.0.2 patch) on Vista 64-bit, PSE restored my backup successfully, but when I hit "okay", just hangs until "not responding" without showing any pictures.  In the meantime my Win7 upgrade arrived, so I uninstalled PSE5 and installed Win7.
When I reinstalled PSE5 (and 5.0.2), now under Win7 64-bit, that same catalog worked!  My catalog was now fine after generating all the thumbnails, and I even moved all the photos using folder view.  I was very happy.  But the next morning, I was back to the catalog hanging.  If I create a new catalog with some pictures, it works fine, but obviously I want my old catalog.  I've tried rebooting, reinstalling, starting with a new catalog and restoring the backup, recovering the big catalog, deleting the thumbnail cache, deleting the status.dat file, looking at the catalog with MS Access, and even more, all multiple times.
Any ideas?  If it hadn't worked the one night, and if it didn't work on a new catalog, I would just assume that it wasn't possible.
Thanks,
John S.

Answer 1

John,
Thanks for the suggestion.  I forgot to mention that I had tried the compatibility options already, but I gave them another shot (on the organizer executable).  Still no luck.
And when I say the program hangs, specifically it displays the organizer splash screen and then nothing else, even though the process (but not application) is listed in the Task Manager.
John S.