As Marvin already pointed out, v2 is fully playable. I'm still tweaking a few things, but that's mainly for balancing reasons, and to improve the AIs research-behaviour.
It currently doesn't work for the campaigns. I want to make sure that the tech trees are finished before I start updating the campaigns, because I would prefer not having to redo everything, just because something changed again.
Just to add to what Marvin said, if you could register your retail version, you should be able to download the newest installer directly from Stardock. This installer should include the update once it is ready.