It's interesting and you can learn some knowledge about some country :)
Those country balls are special for their flag and culture~
And you can open/hide the menu or inventory by right click on the menu or inventory button.
Also the conversation is funny, too XD
By the way, if you get stuck, just ask the Taiwan ball in the last conversation and keep doing that one first( for example, the last is gas, go to do gas mission first), and there are white circle to change different face of Earth.
I have finished it without walkthrough ;)