This is the only one i've not gotten the platinum on.
Well since you said that you're going to have to platinum it now! It's ruining your perfect track record :P
It's the only one we never finished... All the other ones my wife and I finished, yet All 4 One just wasn't that much fun with 2 players. The constant, I want to go this way, no I want to look here problem.
Going in different direction is usually the bane with many coop games lol Just wait until you can play it with 4 players! :D