In reply to:
the MARK button on the remote... if i recall, isnt this stored on the custom scratch partition..
Most likely, it is recorded in the scratch partition. No way the player will mount your drives read/write just to record this button press. Storing this info in flash could be possible, but is unlikely too.
In reply to:
won't the rsync method expose us to the "reused fids" bug?
Yes, probably. But both emplode and mp3tofid will reuse FID numbers, so this is inevitable. If FID's would not be reused, the database file would grow and grow, and the player would consume all memory to read it.
Now if only more was known where what is stored in the scratch partition...