You selected all the maps to upload in MapSource (turns pink)?
The map select tool is pushed in.
The map segments you want to load onto the gps turn pink when you select them and when you upload tick the maps box-
Edit: another idea :
Have you loaded some existing favorite routes into your gps ? Does the message saying that " This Route Does Not Match The Available Maps" come when these routes are loaded ? ( If yes try to load the new mapset into the gps with a new route created on the new map version , may be there is an incompatibility with the new map)
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