Try install browserhax on EMUNAND -> Boot Browserhax -> HBL -> FBI.3dsx -> Install FBI.CIA
If that does not work, then I am afraid you have to go back to the Create EMUNAND step.
Before you create EMUNADN, back up (copy all the files and folders on the SD card to your PC). After the EMUNAND is created, copy back the files and folders form PC to the SD card.
I've thought about trying that, but I'm not sure I'll be able to. The problem I'm facing is that I need my boot.3dsx to be CtrBootManager in order to access the emuNAND, so if I load Browserhax on it, I'll go back to CtrBootManager. I will be able to select the HBL from there, but will I still be on emuNAND? Or will have I "jumped" back to sysNAND?