After opening the .exe and unpacking, it says it can only install to a GPS device, and will overwrite the previous map (img).
I have the current map (CN Thailand NT (Dual) 2014.10) in the /garmin/Map folder on the GPS, but it is named as gmapsup1.img - which I changed to gmapsup1.img_old to avoid losing it if something went wrong with installing the new map. I similarly renamed the patched JCV file.
Connecting the GPS to the computer then ends up with the Error 46 message.
Any ideas would be very welcome.