Is version 4.0 totally fixed by now, reliable and stable?  I'm still using Version 3.9.1 Build 1657 (running Win 7 Ultimate).  I cannot imagine having the upgrade mess things up on my DVD Profiler application as would hate having to type the info for 3000 movies into the program all over again.  Never had a problem upgrading in the past but I recall when v4.0 came out people had lots of problems with it.
Thank you if anyone knows.

Thank you, DJ Doena, for your thoughts on my question.  I ALWAYS back up my collection after I add a new group of DVDs to my profiler and also keep a backup on an external hard drive as well..  No idea how I would exclude my cover images and I wouldn't want to not have them if for some reason I did need to use my backup to reinstall, etc. My collection isn't that large so it backs up rather quickly, perhaps minute and a half.