Marker track import problem

I have a marker track in Cubase, that I want to import into a current flow in Dorico.
I export it as a selected track from Cubase, it is saved as an xml file, but I get an invalid file error when importing into Dorico.
What am I missing ?

Dorico only imports markers from MIDI files at the moment, not from the marker XML files exported by Cubase. So export a MIDI file and then import that via File > Import > Tempo Track.