I have that bug always with a baseball bat, if I have a baseball bat at slot 1 and I directly swap the bat with a hatch from the floor via inventory, I will have a hatch in my inventory but a bat at slot 1 - and I cant use this one.

Lots of buildings, for example the school in cherno when I am right over the doors of the floor below, i can open/close them. Its annoying because on some levels you can't open the doors, but suddenly the "open/close symbol" pops up and you just recognize that its just from another floor.

Well I can't agree. I was with a buddy near electro and he one-hitted a zombie with his axe. Maybe the Zombie was already hit by another player cause the zombie stood over a dead body. But before that he already killed another Zombie with his axe. Don't know how many hits he took then but couldn't be this much cause the fight was over in a few seconds.