I've found a bug where if the game is in fullscreen or maximized when in a level, your aiming cursor will be pulled to the top left of the window.
The cube relic is the last relic I have to unlock in the lobby, and I've found it many times in my runs (sometimes multiple times in a single run), but it never appears in the lobby.
Having a transformation only blocks you from losing. So if you're down to being nude a tf will prevent a game over, otherwise its damage as usual.