The demos are provided here to give users an idea of how MooTools works. The worst thing you can do is to copy and paste code from the demos without understanding how it works. Instead, these demos aim to show you live examples of how the framework is used properly so you can understand the code and have fun playing with it. This doesn't mean you cannot copy the demos verbatim, but we will be more inclined to help if we determine that you understand not only how to copy and paste, but also how the demos work. The demos that work here should also work for you, so if they don't, try to solve your problem before asking for one of the developers to fix it for you.