Good news everyone! I have a (barely) working GUI in-game!
Some parts are missing, such as the checkboxes next to the compound bars (which I didn’t have time to do) and the compound bars along the lower bar (because I have no idea how to make them). None of the buttons do anything yet. All the old elements are still there, they’re either invisible or moved off-screen. Anytime you see any glitchy rectangles, those are also old elements which I haven’t yet removed. The black box in the centre is the old quit button, which I put there for convenience.