OK, here's my wild guess. I assume the first two pictures are different views of the same thing. So I think it may be a pop-up changing room. The first item may be the top that is normally down but can lift up to use the room. The double folding door may go below the top and fold out of the way to allow a person to walk into the room when the top is up. The third item may be the tent-like structure that pops-up (with some human help) to provide a privacy enclosure for the room. .... Just a guess.
P.S. I had a pop-up changing room on my old boat and no one ever used it. That may be why this one was removed.