There is a bug which causes the creatures in act2 to get a very big level boost when you gain experience in the battlefields in act1. It's a pretty annoying bug and my best advise is to wait for the patch.
Regarding the patch, it has been ready for some time but we're having problems with the copy protection. It looks like these are about to be resolved and once they are, we'll be able to release it. Expect it definitely this week.
Lar