I'm sure Thom will fix you right up, but my first thought was that you have a database version mis-match. Many of the AW updates modify the database structure, so your backed up data needs to be the same version as the program you use to rebuild it.

For me the best AW2K backup is a complete backup - the entire AW directory - programs and data and archives - so everything matches - data and program. And I backup often - every day - at least 2 sets of backups.