You asked for these as separate threads so I am doing just that.
The GPX format seems to be one of those common formats yet GC doesn't accept files in that format. GC has no meaningful error msg on uploading that explains anything, so I am assuming it is because of it being a GPX file.
I would like to upload my activities that are saved as a GPX file. MapMyRun or MapMyRide only save in this format, also that's about all SportTracks does, and ditto for OziExplorer.
Jim