I followed a spanish video (I speak spanish), I'll describe what I do:So you tried:
1) SD with EmuNAND JPN region signed in to JPN NNID
2) SD with EmuNAND JPN region with no NNID
3) SysNAND EUR region
If that did not work with the steps provide, I'm not quite sure how to fix it. I will research a bit more some of my notes and let u know what I find.
In meantime, how did you get JPN region to work? Can you describe full setup process from the begginig?
First of all, I dump Nand Xorpads (with Rxtools)
Then I install with the sysupdater the version 9.9 JAP
I dumped my EmuNand with emuNand tool
With Secure_Info Tool, I modified the EmuNAND inyecting the secureInfo Jap and the Nand Xorpads.
Then I inyected the new EmuNAND.
Finally I booted the new Emunand that was Japanese