Of course!! I think I didn't make it very clear on the page (so I plan on changing it later), but using copying code as long as it's for gameplay/functional purposes is 100% okay! 🫶 After all, the code has also been the culmination of many people generously helping others with code!
As long as the images and general visuals are different, everything is fair game. I only wrote it because some people want to respect the author's wishes. If you ever write a Twine IF, feel free to look into it / ask me questions on Tumblr! :)