In the screenshot above you can see the current state of the editor. For the GUI I used the tkinter package for Python, but it is a bit unintuitive to use which makes progress slow. I am in doubt if I should continue with this version or just start over and maybe use a different approach. This started out as a quick test to see how easy it is to make a GUI in Python, but now it has turned into a lot of spagetti code. Perhaps I will restart and first make all the functions necessary to manipulate the *.xml, and then make the GUI.