this is the istruction translate in english that are in the link http://www.cycling-manager.it/forum/index.php?showtopic=9454
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if you want to do your path, that go for secondary street and do with a hand, you must click on add path, that is the third bottom on the work's bar, and then you create your path. after this you save it, you put the name and you save it as kml file (no kmz)