C_major,
Only one of the backup files for this project is good (Mt Tom Peregrines_backup.vpj), but it's so old it's useless to me; I don't know for sure if it was created before I upgraded to 4.10, because the file was created on the day I updated, but I think it was created just before updating.
When I open the others in VP, the media bins fill, as I said. The Video Track1 and Audio Track1 do not appear at the bottom of the screen, and the sequences are empty. If I click on a clip and bring it into the clip preview, then click the green arrow to place it on a sequence, nothing appears to happen, the video and audio tracks still do not appear at all on the Timeline or Storyboard, the sequence preview says the sequence is empty; but the message "Did Action: drop clips to track" appears briefly in the lower left corner of the screen. If I drag a clip from the bin directly to the timeline where the Video and Audio tracks should be, then the Video and Audio tracks appear and the clip is there on the timeline. I can then bring the next clip into the preview and drop it down to the sequence as usual.
I'm not much of a Dropbox user, but I uploaded the latest vpj file (Mt Tom Peregrines_backup(25).vpj); hopefully you can access it at https://www.dropbox....p (25).vpj?dl=0
The old backup that does load (Mt Tom Peregrines_backup.vpj) is at https://www.dropbox....p (25).vpj?dl=0
I did not upload the media files, they're too large and too many.