My brother has a works tomtom one, 512 internal memory, no SD card slot.
The Navcore is 8.080
I can see not get a Canary Island map (holiday on Sunday) to work at all.
I have a really old Canary Islands map (from a TT910)
I have also tried the Iberia maps 855.2931, and 855.2884
The tomtom will not accept them.
I have been using fastactivate 1.4 and Easy activate.
As it is a works ...