Coop Instances

I noticed on multi-player if the party leader doesn't create the new instances first and or gotl to knew areas fist; then the instances get mixed up. Sometimes you can or can't warp to each other to fix it. Also this locks you one player out of quest steps based on who's instance it is I think. In act 2 your quest steps are separated and you both have to interact but you don't get locked up by what the other player is doing. But in parts of act 3 you get locked up sometimes have to re login to clear it.