I have a TomTom Start 25 with the proper internal microSD card. Home computer is Apple/Mac with TomTom MyDrive Connect. The microSD card is recognized and was formatted. I can't figure out how to back up my map and Favourites to the microSD card. I'm not understanding what the purpose of the microSD card is, if not for backing up my Map(s) and Favourites. There's adequate space on both the device and card for everything. So confused.