I know this topic is very old, not sure if its been discussed again.
I'm not technically knowledgeable about GPX, but
If I use 1.1 transferred to the Zumo via Drive it saves it both as a track and a route. Which seems a good option.
However 1.2 only transfers as a route?
No idea why but does the change which is the better format if you wish to follow the exact route as planned?
I'm usually happed to just follow a line as long as I'm taken the correct way.