Plarail TOMY Thomas NEW RELEASES

Are the tracks and scenery at displays like this normally held down with shiny dome-headed screws the way they are here?

Yes, they are, for some reason (stability?). I saw small shiny screws on many official Takara Tomy displays so far. They are not to be seen in the official Tomy videos, but when visitors are shooting the videos, we can see these screws. Here are the screws in a 2018 Expo video:





And you are most probably right, Chrisjo: the sheds are a representation of the big roundhouse and turntable at the museum, which originals can be seen in the first part of Suzukawa's video.