Alternate Warfare is a Total Conversion on C&C3 engine, the background story is set in the Cold War era in a different timeline, in which the experimental weapons that never practically saw service are granted a chance to prove themselves in the battlefield. As the Commander, you will have to battle through a series of campaigns dating from regional conflict in the 70s to a full-scale nuclear war in the mid-90s, make use of these new weapons wisely in order to emerge victorious in this Alternate Warfare.
The v0.20 in fact is already released, but is still awaiting ModDB authorisation. so if you can't wait you can get it at the official site.