Yes, i'm acutely aware of the lack of compatibility of my current product. but i am wondering if i had a device compatible with third party maps, such as a gpsmap 7000 with older firmware, would openstreetmap work, or is there something inherently different between street and nav maps which would prevent compatibility? I intend to use this chartplotter for off road expeditions....right now trying to decide if it is worth reverse engineering this device, or exchanging it for an older device capable of doing what i want to do.