OK, I am now officially the happiest DVR-108 owner alive.
I flashed the firmware, figured it was worth a shot.
I just backed up a game, first try. I'm not TOTALLY sure it was the firmware, because I backed up a different game than I was trying before. However, my brother tried "backing up" a couple downloaded games, and tried to backup a copied game, and none of them worked.
I'm going to try to re-burn the game I've been working on... if that works, that guy's getting a nice donation :D!