Help!: importing routes from Google Earth

Is it possible to import a KMZ file from Google Earth? You can obviously EXPORT, but what about routes and GPS waypoints that you create or upload into Google Earth from a GPS and then save as KMZ FIles.

 The mapping tool in Google Earth is much more feature rich, and I would love to use that as my primary mapping tool, and then import the routes into MapMyRun for the tracking features.

Alex Taylor - alexandtaylor@gmail.com