After the first 1.5.7 beta, there were some complaints that the AI was being too competitive with each other regarding sheep, so we’ve released a new beta with all the bug fixes in 1.5.7 beta 1, with a little tweak to the way AI treats sheep. Hopefully this will alleviate issues some players have been experiencing.
The new beta can be found here. All you need to do is install it over your existing copy, and you should get the latest updates. Let us know if you have any trouble.