It's because games made with older versions of GMS don't run properly on Win10. There is a fix called "gm8x_fix" for running Gamemaker 8 games properly and another one that I use called "melatonin" that fixes problems with all GMS games in my experience. Not sure how easy it will be for you to find them though as I got them through the "I Wanna Community" Discord.
Really? Thank you!!!
I honestly really appreciate that you took the time to write that reply even though my original post was 266 days old. I know I've encountered that same issue with other games too (I think the original Momodora game from 2010 was one of them), so that info will certainly still be extremely helpful for me! Thank you!
Edit: I'm really good at google searching, and despite using special operators and syntax I literally cannot find anything GMS related by the name of "melatonin", so I guess I'll try the Discord.