Quote: "It was from you I got the idea Kravenwolf."
Well to be fair, I got the idea from Resident Evil XD
I see what you're seeing though. In other parts of the game (and in the Nazi Zombies Fan Game), I had the same problem with multiple objects in the same segment space. I fixed it by moving the trigger zones into the walls so only a sliver of them was sticking out in front of each entity.
In another game I was working on I decided to use planes as you're working with now, but I just stuck them inside the walls near the scene, so it didn't matter weather or not they were visible.
Kravenwolf