Does things differently??

[Roy Dennis]

The trouble is not all versions are backward compatible with one another.

A number of different things get added to the database, sometimes it's extra fields data, in some cases it can be just where people requested different genre to be added. All this extra data is stored in the kma headers. If you added one of the extra genre then that is stored in the kma file then when you run those files through an earlier version that wasn't listed in the earlier versions that can cause problems but most of the problems occur when extra fields of data are added because the database of the earlier versions can't read these extra fields.

If you load an early version into a later version it updates the kma header with the extra data but then that kma file wont be compatible with the earlier version anymore.
Unless you kept a backup of the original.