Okay... I was able to transfer a couple map segments to the data card with Mapsource. And when I put the card in the eMap and started it, I didn't get the error message about the card being locked as I had before. But the 'Mapsource' menus on the eMap are still grayed out and not highlighted. So the GPS isn't seeing the data on the card. When I zoom into the area of the map where I'd put data onto the card, there's no detail.

My other problem is that Mapsource doesn't see the eMap connected to the serial port. MS Streets & Trips does. But Mapsource only recognizes the data card reader I successfully got working with the eMap's old USB drivers. But if I could get the eMap to recognize the maps I can put on the data card, that wouldn't be a problem.