@ Turbo

-> 3- Why do I get a "Cannot open USB port" with my 3750? Do I need a service cable or do I need to put the GPS in a special mode?

This function is for older garmin devices that support garmin protocol for communication like etrex, gpsmap etc. where POIs and maps are stored in a non-accessible part in the memory.

BTW maybe you will be interested what I have wrote here:
Code:
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