Thank you for your well putout feedback!
May I ask if there was a problem with the game not being able to connect to others or just other general reasons?
Yes the player's colliders are a bit bigger than the visuals that's because it makes it easier to hit players but that would be a simple fix.
Room doors are exactly the player collider size so by fixing the player collider this would be fixed too.
In terms of UI issues, I was experimenting with a new UI tool (Unity UI Toolkit) but it was too complicated for my purpose and I only had 14 days to make the game so had to ditch lots of UI stuff. I am however making my own UI tooling to use in my future games & to remake the UI in this game as well.