It seems that perhaps GunTneR 1.2 may not work right on the NES core. When I attempt to play it the controller mappings are all wrong and glitchy. I saw that some streamer was able to play the game fine so I'm not sure if the problem is with my setup or a new update. Is someone able to check if this game works? It seems like a lot of fun
EDIT: Disregard this post! I mistakenly used the old github build of the game which is out of date (I had misread the date) sorry for this 