Alright, I had the 022-2634 error when trying to log in with NNID, so I followed some tutorials that adviced backing up emuNAND, formatting emuNAND from the system settings, setting up everything including NNID and then injecting NAND from the .bin.
As I formatted emuNAND, I set up everything up and then it asks that I press the HOME button for going back home. After doing this, it shows the Home menu is preparing, and then the screen turns black. After waiting I just reboot in emuNAND (I'm using Rxtools with N3DSXL) but the screen keeps black. I don't really know what is happening. At this point I just injected NAND from my backup and tried it again, with the same results.
What is the FW version if your emunand? Check after restoring the back up but before formatting.