kwikbb, will do!
This afternoon I started going through the codes. I started from 9111 and I'm up to 9355. I should be able to get through the rest of the 9xxx codes tomorrow, then I'll work through the 0xxx codes.
So far, there's no new tricks coming up. Each code seems to do something to the car, like alter the speed, turning, brakes, etc, but nothing that can't be done through the standard settings from the looks of it. But I'm not even 1/4 of the way through the codes, so hopefully something good will turn up!
I also miscounted the total number of possible codes. Since there's no zero or 9 for the last three digits, there's only 1024 possible codes, not 1556. Oh, well!