There is a way to copy code from one world to another. First get all of the code into one piece, such as a "do in order". Then copy it to the clipboard. Do not try to copy an entire method from the properties tab, this will not work.

After that is done, go to File>Open World and open the world you want to paste the code into. The file you copied to the clipboard should still be there. Create a new method, if necessary and drag the clipboard to the method.

However, this will only work if all the objects are already in the world. You cannot copy an object from one world to another, and cannot copy a method that has references to an objects that is not there.