Join Date:Joined: Nov 2011
If you plan on flashing over the internal OS, there is no need to register. When I got my nook, I made a bootable sdcard with CWM, booted into it, mounted to my PC, transferred CM7 to the internal storage and flashed it. From there I eventually flashed CM9 and only saw the B&N OS when I tested albert's nandroid backup.
tl;dr no need to register if you plan on flashing a rom.