26 Dec 2020, 12:33

Probably for the same reason Garmin corrupts TomTom routes, and often even Garmin routes... Importing routes from any platform to any platform will introduce "corruption" as you call it. Fact is that any platform will calculate the route between routepoints as it sees fit, given the many parameters like map and settings.

Mostly I just import a track from the gpx, and redraw the route myself. I think that it works quicker and more certain than any automatic import function.