Well basically get Marshals negotiations in place and antebellum before the Nationalist Offensives Both sides thought they could win. But Both have major problems in Power projection.
http://www.britannica.com/EBchecked/topic/111803/China/71834/Civil-war-1945-49
The Nationalists wasted there best forces in an Offensive, Give a few years despite the Norths greater access to originally getting more of the Industries and coal and oil. I can see in just a few years the will to fight reduced.
I can Imagine the Nationalist South doing well and imagines a Taiwan like Industrialist Post war growth given the size and scale becoming a major power. Does this Take the position Economic position of Japan had in late 1960s, till before the Great economic growth of Current Chinese power house.
Also can see the Nationalists having less will and more wanting to keep on the side of the West staying out of Tibet already mentioned.
Side effects like a different situation in in Korea. and a much smaller Communist China.
There is allot of Western Post war weapons that can go to keep China supplied dirt cheap and if they can manage to keep close relations with the US, can see a Southern China becoming the Main bulwark in Asia against Communism.
Now how this effects Japan with no Korean war to become a Major base and getting less support rebuilding Infrastructure and what happens in Vietnam ??,
This would cause Major Butterflies and a very Different Asia pacific.