You can add a column to the options database named `ownerid` which is int(11).
It might be best for you to upgrade to the nightly build from last night. I believe this build will automatically fix this issue.
Anyway, back to your first question. If you do not change the album structure of your gallery, just reload the albums and images via FTP. Just to be safe, once you have them all uploaded, run a Database Refresh. This will clean out any database entries that no longer have images/albums in the folders.