Good you pointed to it. Before it was possible to plan a route in Skydemon, go to Information and click Explore to see the GoogleMaps overlaid with some features and the magenta track line. Somehow the magenta line on the GoogleMaps disappeared, why?
Checking in GoogleEarth can be established by planning the route, go to Route - Share - Mail and send the planned route to yourself. In the mail you will find a .gpx file, which you can easily import into GoogleEarth.