I've not actually got StreetAtlas so I can't try it out but maybe we could hack something together which would be simpler.
If we use the Lantronix COM port redirector then we'd just need to write the GPS emulator software which can listen to a network connection. The current one wouldn't work unfortunately as it's written to talk to the COM port directly. It would save the hassle of using a null modem cable.
I may actually try writing a basic GPS emulator as the protocol isn't that complicated. It's just making it understand all of the different commands to fake a Garmin GPS.
- Trevor