I am on the iPhone XR with version iOS 12.3.1, and when I went to a custom room, which is a YouTube template, I noticed that the curtains that I made specifically for the stage is missing two of the curtain pieces. I originally made the curtain on my PSVR and I had no problem with it whatsoever. If you want to check it out, the room name is ^test0000000000000000011, and it’s owner is @Braperez (I am the co-owner of the place along with another friend of mine.) I’m not sure if this happens when I’m alone or with someone, but I think it happens regardless on mobile users. I’ve added a photo so you can see what I’m talking about. (Because this stage had a giant Trigger Volume, I had to turn the gadgets off so you could clearly see the curtain.)