Multi Switches to open Multiple Doors
by Turbo Pascal and Aktrekker

This is how to have a number of switches open different doors, depending on which switches you operate, similar to the set up in the Palace Midas level of the original Tomb Raider game.

It doesn't matter which code bit sequence you use for the first switchtrigger, or the second switchtrigger, you just have to make sure that when you've pulled all the switches, that 'the sum' of all the code bits in all the 5 code bit places is 1. 
And some different maths apply here as we have to work in binary:

0+0=0 
0+1=1 
1+0=1 
1+1=0

For example (with 3 switches):

switchtrigger #1: 01101 (place 2, 3 and 5 are pressed, place 1 and 4 are not pressed) 
switchtrigger #2: 10100 

When you add these settings up, the result is:

01101 
10100 
11001 

So if you set switchtrigger #3 to: 00110, the final result (when you pull all three triggers) would be 11111 and the object with (triggers on all 3 places) is triggered.

The Exception

The result of pulling different switches doesn't always have to be 11111. When you open the OCB panel of an object, you will see that there are 5 code bits. You can press them, and these settings will also affect the sum values when added to the switchtrigger settings. 

For example (with 3 switches):

switchtrigger #1: 01001 
switchtrigger #2: 10101 
switchtrigger #3: 00010 

So the end result of all the switches is 11110. (It doesn't necessarily have to be 11110. It can also be 00101, 11111, 11100 etc) 

Now, when you have 3 doors that need to be opened at different times, you can use the OCB code bit of the object. 

door 1: 00011 
door 2: 01000 
door 3: 00001 

Then you place triggers for door 1, door 2 and door 3 on the tile of switchtrigger #1, #2 and #3 (so you place 9 triggers!). Now you just have to add up. 

Let's say you pull switch 1 and 2:

switchtrigger #1 + switchtrigger #2 + door 1 =

01001 
10101 
00011 
11111 and door 1 will open. 

switchtrigger #1 + switchtrigger #2 + door 2 =

01001 
10101 
01000 
10100 and door 2 is will not open because the end result isn't 11111. 

switchtrigger #1 + switchtrigger #2 + door 3 =

01001 
10101 
00001 
11101 and door 3 is will not open. 

So:

door 1 opens after switch 1 & 2; 
door 2 opens after switch 2 & 3; 
door 3 opens after switch 1 & 2 & 3 AND door 1 and door 2 will close when you pull switch 3 (because the code bits don't add up to 11111).

For further help, please see this flash video tutorial by Pemon:
How to set up multiple levers to open multiple doors