Thanks for picking this up. We'll get it changed.
The exported KML file has a wrong structure.
Right after the LineString There will be Placemarks for Start/Finish and for each kilometer (if chosen on export).
On that point forward the KML file has Style elements WaypointMarkerStyle and DistanceMarkerStyle. These Style elements are on the same level as Placemark. The have to be placed one level higher, they have to be inside Folder element.
Currently these style elements are ingored as the file structure is wrong.
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