I also use a PC and Windows 10. System updates have caused me some trouble with my Wacom… and nothing compared to your problem! I don’t recall ever messing with this script window; yours should look like this:
In these cases, when you install and reinstall a program… and it still doesn’t work properly, the best option would be to use Revo Uninstaller: it completely removes a program, leaving no traces. Once done, you try installing Krita again.
I’ve only had to use Revo Uninstaller once or twice and it worked well. I can’t promise it’ll be a solution, but I don’t think there are many other options…