So the problem I found is that when you try to click the highlighted icon seen on the screenshot, the game crashes. This doesn't have anything to do with the entirety of getting images, since I dragged and dropped my image file in there and it worked just fine. The problem specifically has to do with clicking that icon.

New Release
https://www.curseforge.com/minecraft/mc-mods/iammusicplayer/files/3487094