Okay, don't do what you did to the script. On the line that checks the player's dist from the door add this condition.
Believe it or not, the door and any other entity, CAN see the player. Non-character type entities are simply hard-coded (by default anyway) with a 360 degree viewcone angle. This means it is looking in ALL directions for the player, and it will NOT see the player through walls, ceilings, floors, etc.
I used THAT specific command because since you're making a multiplayer game, I'm assuming no AI will be wanting to use the door, lol.
Hope that works for you, cuz it works wonders for me.
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Dammit, Jim! I'm a programmer not a graphic designer!!!
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