The game is broken when it comes to resolution. When opening it in my massive 32" screen the window opens with half the menu off the screen. It scales all wrong. If I attempt to play it on the steamdeck it's unusable as you can't even use the main menu as the menu is off the screen. As it looks like you used unity for this game you can fix this by going to your config settings and set screen resolution to a standard size for the game. These are bugs that can be fixed with a few clicks. Please fix this.
