two things i've noticed while playing the pre release on an island base
mobs do not recognize that they can jump onto blocks. I had to use slabs and physically push my cows to get them onto land after getting them out of a boat
It's very difficult to get out of a boat with another mob. I will press shift and it will glitch me to where I look like I'm "vibrating" above it for about two seconds before it shoots the boat backwards a few blocks and I'm on the shore where I got off
Please put separate bugs on separate reports, unlike what you did here.