Having dealt with the map issues the Montan 7xx series has, I installed the CN EU maps on an SD card, that worked fine in the beginning, and then all of a sudden the maps disappeared and only square blocks with map segment numbers appeard, powering the device off and on did not help, removing the sd card, starting the Montana, shutting it down. inserting the SD card again and it worked again. So after this happend a few times I was thinking of a faulty SD, so I ran several tests on the sd card to see if there was an issue, none whatsover. I copied all that was on the card to another brand of sd card, put that in the Montana and had no issues anymore. The lexar sd card works okay in any other device, and reports no read/write errors whatsoever. I think it's a compatability issue.
