I can make recipes just fine - I do acknowledge that I need to restart - but even if I do that I can't remove recipes. I remove a recipe multiple times and it just stays there when I restart. I downloaded a program that can use ZS files like what MineTweaker RecipeMaker uses, but it just says there's an error with the file and I can literally do nothing else with it unless I close the program and then reload the file, where it just starts that part over again. I have to delete the ZS file to remove the recipes I don't want, but that means having to reapply all the ones I do. As a side note, I'm currently using 1.12.2 - it's the latest version for Curseforge.

You don't need a special program for ZS files. Any text editor will work.
Recipes you add are always there. You can't remove a recipe you add unless you delete it from the file.