Interesting way to post a team request, but ...
To have three switches activate a door: (In any order)
1) Have each switch activated the door with a number
2) when that door detects that it's been activated, have it increase a variable (You can use "state" if you don't have the latest updates and figure a way around using it to open the door)
3) Once that variable reaches "3", have the door check for the key
4) If the player has the key, then open the door
To have three switches activate a door: (In a specific order)
1) Have each switch activate the door with different activation values. (Switch 1 will activate the door with a value of "1", Switch with a value of "2", etc)
2) When the door is activated with the correct value, it increases a variable (Again, use "state" if necessary)
3) If the door is activated with the WRONG value, then reset the variable to 0
4) Once the variable reaches "3", then check for the key
5) If the player has the key, open the door
It's not a hard concept to grasp. But variables would make this much easier to script.
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