In version 1.11 noticed that zombies are not crossing and DOES not react to the player if he is behind the railway. When I'm with zombie on one side, he sees me, comes forward and tries to attack, but if I go over the railway, as zombies cannot go through the path. So he stands and waits. But holding me at gunpoint. Also it seemed to me that in 1.11, adults, zombies are not (can't or don't want) through the open door. In this case the zombie children are. A similar picture with the creeper: I have something like a horse corral - a fenced enclosure with a height of two blocks(simple wooden fence), and something like a gate (double door). So creeper was behind a fence, he saw me, went behind me, came to open the door, looked at me and went, then turned away and left.
P. S. I'm from Russia, English is not know, wrote with a mechanical translator can therefore be inaccuracies in the description.