I'm sorry I don't know if someone already made this but, I have an R4i-SDHC with the 1.12d firmware. I am wondering if pokemon white 2 will work on it since I have been getting the errcode=-4 error.
All games work on the card its just not the pokemon white and black 2.Do other games work with your flashcart? Is it a clean ROM? If it's not a clean ROM, I suggest you download and try a fresh copy. If that doesn't help, RetroGameFan's software might help, if only a matter of troubleshooting.