i have the N1, with the N3 upgrade, which disables dvd, and navigation when your driving past 5 mph.
to re-enable the dvd, navigation while driving, there is a soldering mod/hack that needs to be done, i have never soldered anything on a circuit board, so i am looking for someone in michigan that has soldered on an N1 before, so i can Pay them to mod mine.
i've re-read the first post and its pretty well explained in that one.