I am doing my second playthrouh now on version 2.1.1. Did my first playthroug on the former release without a hitch (Except the bug with EU not being registrered). But passive mob spawn worked fine in the overworld. Now I have had 3 25x25 grass block areas in the overworld and have not had a single passive mob spawn. Have had the areas for the past 3 hours trying to spawn the mobs.