I have lifetime maps so I am able to download the map to my PC for use in BC.
I have just checked to see where it was put
C:/programdata/Garmin/Core Update Service/Map xxxxx2013.30/xxxxxxxxxx.img
But I think this structure was generated by the "MapInstall" app from Garmin when I downloaded it to the PC.
Unless anyone knows better, you may have to use BC connected to a device to view your map.
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