To unlock just use gimgunlock, look at
[Only registered and activated users can see links. Click Here To Register...]
You can see the map easily with Basecamp, just put the map on yourGPS or usb or virtual disk (in the right directorie: Garmin). For use with Basecamp and usb or virtual disk, You don't have to unlock the file.
For using the trails you must put the .db file in the SQL directorie.
For use with Mapsource you must split the file with GMapTool. Install the map as a Windows-registry map or make a gmap-version with JaVaWaMapConverter.