Has anyone ever succeded in combining two garmin compatible gmapsupp.img maps into one, so the two can be selected as layers on the divice without the need of a PC to change/rename files on the SD card?
I like to use the raumbezug OSM map for Garmin for in car routing, but also the hiking maps for, well, hiking. It would be really cool (and should be technically possible) to change between the two on the fly.
So can anyone help? How to combine both into one gmapsupp.img?