Thanks! That sounds (very) promising

. My confusion stems from a piece of info I received from Garmin. If I interpret that info correctly (perhaps not, because I'm not familiar with various Garmin mapping products), then this is not supposed to work at all. Garmin Mobile PC is supposed to work only with the map data it comes with. Here's the link to the
Garmin Mobile PC compatibility with other Garmin map products (post #65).