could you explain me how you can mix all maps and working?? I have all maps in my zumo 550, but I must to put them in two diferent maps, one europe NT 2009 like a gmapprom in the memory of zumo, and other all the maps like a gmapsup in the SD card. If I try to do a single map in mapsource, my GPS can´t recognice it.
There could be two possibilities why its not working for you:
1) You are not familiar to use to mix maps in mapsource
2) You need to put inside the *.unl txt file all the codes from each map in coleration with the unit ID code.
P.S: have you read carefully my install info on the first post?