We don't need to identify what business use is because that term is not anywhere in the license. All we need to know is what "commercial use" is. As long as you don't take someone's code and try to sell it as your own, you're covered. That doesn't mean you can't use any the code, it just means you can't pass if off as your own. Keep the copyrights in the script (if provided), or add a note that the script was obtained from SDU to give credit to where you got it.
Sure you can change the code as you mentioned, and who would know? But that isn't necessarily a shelter. You can't just rename Window