The technique here is to use a general purpose input that can be a "contact" type. Give it a custom name. Then you can set your color ranges and states within the 0-5V range that the input can read. So for an on/off or two state switch that goes open and ground, you set one state to be 0-3V - this is ground, and the other to 3-5V - this is open. The 3V is arbitrary, of course. It'll either go to 0 (when grounded) or 5 (when open). You can then name the different states.