I am using a Mac; I downloaded the file, unzipped it, opened it with Map Manager, and used MapInstall to select the portions I wanted to install and send it to my Dakota. It went through an install process, and there is a gmapsupp.img on my device, but when I turn it on, I just get the error message "Can't Unlock Maps"
I've tried changing the name of gmapsupp.img to something more memorable, and I've also tried installing it on a memory card instead of the unit itself. I've also tried a couple other Colorado maps, and I can't get those to work either (same "Can't Unlock Maps" error message).
Any advice would sure be appreciated.