It's not enough to just unpack the ZIP's, there are sometimes other things that need to be done (in particular, running ArchiveMaintenance.exe).
Did that, but not between alpha 1 en alpha2
You did back everything up first, right...?
Otherwise, delete your user's ARCHIVE.DB file and that will *probably* be enough.
That did indeed the job. Lost a few titles, but anything is better than losing it all. Thanks for the quick response