I could not replicate the exact problem that you describe. But I found that none of the move stimuli displayed in either Chrome or Edge under Windows.
I found that the cause of your problem was primarily the choice of units in the experimental settings being height, when you seemed to intend to shift your movies by 400 pixels sideways. Effectively, the movies were shifted off screen. I fixed this by changing the units to pixels for the movies (it is best to leave the global preference as height to make text sizing easier).
I would also recommend that you resize all of your movie files to their display size of 720 by 480, instead of the 1920 by 1080 as they currently are. Free tools such as Hand Brake are an easy way of doing this. That will allow your online experiment to load much quicker.
A current quirk of movies displayed online is that a static image remains after the movie has finished playing (this is discussed elsewhere), which does not seem to be what you had intended to happen. I solved this problem by overlaying each movie’s location with a rectangle of the background colour with the same size and location as each movie. Each rectangle appeared 3 seconds after the beginning of each movie, because all movies seem to have a runtime of 3 second.
I have made a minimal public example experiment based on your full experiment to demonstrates all of these fixes. Please try it out, see axel_e_expt_fixed_example.