That makes the WINDOWS key not work, not alt-tab. alt-tab is built into windows. Key broadcasters can eat it, but that is about it. My alt keys are built for doing things to my main char (cast-on-self keybind). I don't do that too much, so don't use alt so much. Maybe you can change your cast-on-self keybind to another key so you won't press alt so much. Also, you might use the option "cast spells on yourself by default". That way you don't have to press alt much either. Good luck.