I too, have noticed some strange pathing behaviours. I think what is happening here is the Zs are finding a different path to you. The AI might be getting tricked into thinking its easier to bust through a door or walk around an edge (looking at YOU, "coal factory") rather than take the direct path to their target. Still unsure if its intentional, but I like it. Zs cant be that intelligent, right? What with their mangled and decaying brains. So for me, this adds realism and a bit of surprise. I don't want my Zs to be totally predictable - that's how cheese is made.