Big Kahuna Reef code transfer - anyone?

One of the few games I like to play on the mac is BKR. I have a fully paid up version it on my old G4. I migrated that account to a G5 I have acquired and although the game fires up fine and all the levels are as expected, it is in the 1hr free test mode - it doesn't appear that my "activation code" carried over in the migration. If I click "already paid" it asks for the code again.

Anyone got any idea where that may be stored on the old G4 (10.4.11) and how I can see or extract it?

Otherwise it's back to the sofware supplier