PM sent! SNO
I purchased GMPC just as they discontinued it (thanks Garmin) but got it with the x20 antenna so no need to call the wonderful Garmin support line.
Now the x20 antenna seems to be taking longer and longer to acquire signals and I'm trying to make the software work with the Sure Electronics antenna.
When I place the SW.UNL in the c:/garminmobilepc directory all I get is a completely black window when starting GMPC.
It doesn't respond to mouse clicks as if only the image was missing and the buttons are still there, the only thing to do is force close the window.
Remove the SW.UNL and everything works but I can't have it read the new antenna that way.