Thanks for your reply.
Just to clarify, I don't need more than one video tracks, just more than one file in the SAME video track.
Does your answer mean that it can read a video track with two files on it but not import a third video file (at a different location on the timeline, ofc) into it?
Strange that I can open a session with more than one file on the video track but cannot just import any more files into it
Best,
R.