How to add a city in map cloner?

I'm trying to make a custom map, and I am cloning off the default world map, but every time I add a city, I always get null, and it varies, whether I'm trying to save it or place it, and it always links me to the java script right here: http://atwar-game.com/java/game/atwar.game.min_v34.js
So how do I add a new city without this problem?
I used chrome, explorer and firefox too and have gotten the same problem.

The fact you called it a cloner made me sick to My stomach.

Your issue is your using the html5 editor which isn't operational, you'll have to figure out how to get the Silverlight version in order to make maps.