Your current map is probably unlocked to the SD card ID, so it would then give the 'unauthenticated' message if moved to the unit. Your basemap [gmapbmap.img] and Time Zone map [gmaptz.img] should be put in the zumo's .System folder though.

Glad you're finally sorted anyway. A bit of a marathon effort for you but these recent posts may help some others attempting this conversion. Cheers.