At 1:48, you say "First attempt of importing XML into empty project gives nothing"...but you don't have the Project panel open, so how could you know? At 2:01, "Second attempt with a file already in the timeline gives no better results - no markers in either case". You just imported an mp4 file, by dropping onto an area that says 'drop here to create new sequence'. You now have a new sequence, containing no markers. Prediction; if you show your Project panel after 1:48, you'll see a sequence, WITH your markers.
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