There are some games with 9.2 firmware, so you could use them to update your 3DS. The two I know are Super Smash Bros. 3DS (although, apparently it's only the early copies of the game) and Cooking Mama.
I don't think this question has been answered yet; will ARCode work with regionthree?
I have a European 3DS on 9.5.0.22E without a Gateway, the best thing I can do to play and use ARCode on SMT4 and Rune Factory 4 would be to import the US versions.
I meant the actual save data. It seems you won't be able to use the ABXY method straight after the backup is injected, so you erase the data the other normal way by asking Isabelle to "recreate the town". Not erasing the save data before quitting to the home menu leaves the 3DS hanging on the...
I had the same problem you had for a past week; I bricked my copy and the ABXY method didn't work at all.
But somehow, I just fixed my game today. It looks like the Save Restore from NeoKamek's thread fixes the problem if you use it in the loading screen before the error happens.
EDIT: Make...