Arrghhh!!!
That bites big time.  I've also had a game I've auctioned
scratched(twas a CD ROM.) Luckily, it still worked
perfectly.  I spent about 20 hours playing the game straight
through to make sure it worked perfectly.
I still told the high bidder what happened but the game
still worked.  She bought it, it worked for her, ironically
her young children got into her game stash and ruined a 
bunch of things, and smashed the game I just sold her.
Ironic, ain't it?