I encounter the problem with BC that it gives errors on Mac files.
Especially files like ._RouteName.gpx or .RouteName.gpx in de \Garmin\Gpx\ directory
These files are probably deleted under my Mac, but BC for WIndows gives errors and crashes or does not respond anymore.
These files should be ignored.
In the meanwhile, using NINT once on your GPS and microSD cards can help to prevent this
(watch out, the translation from dutch to english is not very good :) )