One of the more experienced people can correct me if I am wrong, but I think you should be able to do this using Nook Manager
. You would have to prepare the SD card (make sure it is at least 2GB) before ever turning on the Nook. Insert the SD card and power on the Nook (perhaps while attaching the charger at the same time). Unless I miss my guess, it will boot from the SD card and you can then follow the Nook Manager prompts to first backup
and then root the Nook. I believe this procedure would allow you to root the Nook without ever registering it.
If this does not work, there is a way to boot the Nook without registering it. I don't have the link to this at the moment but you should be able to find the procedure with a simple internet search.
If you do this, it is likely the end user will have to run registration app manually as after it is rooted, it probably will not run automatically.
Here is the link to how to boot a NST or NSTG without registering it. nook touch skip registration