I made a question on Noob paradise about region changing too. If you don't mind me asking, is it actually still possible to switch 3DS region without 3DSNus? I'm very, very interested in switching my emunand language so I can install a couple of Japanese dlc, and I don't care about online, so I might just install a Japanese emunand on a 2nd SD just for this, assuming it's possible. If you do try using your secure info A, it would be great if you could post about it here. I'll probably try to find that file too,, but I'm still really new to high level 3DS hacking, so I'm still on the fence on whether I should switch my emunand region, or just fork over the cash, and buy a gateway.
Actually, it might not be that useless if you don't have gateway and enjoy playing Japanese games. Unless I messed up somewhere, looks like despite the fact you can play games region free on RXtools, you can't really install Japanese DLC for your Japanese .cia games.