i kind of like the mish mash of themes and objects for this game aesthetically--it feels kind of abstract and pop art-y. i'm curious to see this game in motion--if you get the chance to record gifs or video i'd love to see the mechanics in action!
i'm not familiar with gamemaker but scores are generally saved as variables and then if the program supports text drawing that as a string or text to the screen/ui. there are probably some explanations for that in shmup style game tutorials.