It will be rebuilding the cheat file, then just freeze midway through and the little S1 thing in the corner will stop flashing. I have one of the Acekards from the defective batch, needing to run on 4.07c
You should use AKAIO - http://forum.romulation.net/index.php?topic=38335.msg695431#msg695431 It's WAY better than the OFW, and you can use cheats without it freezing. Plus it fixes the Dec 09 batch problem.
The first time I used AKAIO, it wouldn't work. I was using the 1.6 release. EDIT: Now the cheat file STILL doesn't rebuild. I just download both the cheats.xml AND the cheats.dat from the official site. GOD DAMMIT NOW THE GAMES WON'T EVEN LAUNCH.
The 1.6 release didn't work on the defective batch. 1.7 does. Do yourself a favor, really. Download AKAIO, it will work. Also, format your microSD card.