In your video, look at 5:25........watch the 4 way. It looks like the top of the 4 way, the piece that slides up and down on the tube, looks like it's tipped downward, by a lot!
I understand the shavings between the main wedge and the 4 way post, mine does that as well. I would expect it to move a little when you were hiding it, but what I'm referring to is when you are near the top of the stroke.
Also, go to 11:40 in your video. You can see how much that angle changes from when you do from near top stroke to hidden. That wedge shouldn't move that much. The 4 way should be parallel with the main slide plate. Maybe post a picture close up, on the side, capturing how the wedge it attached to the cylinder. Something isn't right there. Just saying and trying to prevent something from happening that could cost you in the long run.