I can confirm. prerelease two.
I made sure my xp grinder was up to wiki specifications, and I did all kinds of troubleshooting. neither of my zimbie dungeon spawners work. They rotate at the same speed, consistently.
Confirmed. I just fell into a nether lava lake on my survival world.
I confirm. That error message was also responsible for breaking every item frame in the world.
if you are referring to how you have to use 1 lead to leash the animal and another to tie it to the fence, I do believe that is on purpose... But if it is a bug, I confirm its existence.
I can confirm. 1.9 pre 2. It's consistent.