The buttons seem to be here, but when I see only the game and nothing else of the itch page, then I can't scroll at all. So the first time I got stuck "too up" & couldn't see/access them.
Just double-checking: are you saying that the UI buttons for the scene are working for you now? I am currently going over our list of reported bugs (internally and on Itch- we're 8-10 hours apart in time zones on the team!), and this was one of the tricky ones I was setting aside for this afternoon.
Yes, the buttons are here, it's just the window/iframe for your game seems to be too big and there's no scrolling possible. So you can get stuck seeing only part of your game, not seeing the buttons, and having to reload the internet page to do anything.
I think you can solve this by enabling scrolling & the fullscreen button on itch - sth to tick on your game page under where you upload your web-build.