I've downloaded the US20 3 times (don't ask). Using my reader I loaded it to my micro 2 gig. They show up there in their garmin folder on my pc. Insert the card into the gpsr and I can't get the thing to find the mass storage device - when I try to "setup" it goes to the mass storage icon and stays there. Tried both the garmin and NMEA Data format - neither will allow setup of the mass data storage and ability to setup the ibycus USA 20 map onto the gpsr.