Each KIB controller (light switch) is specific to what it controls. So, if you have one, like the kitchen controller it turns on the water pump, counter lights and maybe the overhead lights. It has a model number on the back side. If you were to order that specific controller from Newmar, by that model number, and then install it in the bedroom, it will still turn on the water pump, counter lights and overhead lights.
You can't create your own control that has specific things you want to turn on and mount somewhere in the coach. You can only buy a controller that is already available through Newmar. No custom controllers.
The most common addition is to buy that kitchen controller and mount it to a spot that is more easily accessible than where Newmar installs them, such as the link provided in the post above.
Since each controller is kind of like a minicomputer, all you have to do is "tap" into the grey shielded wire running around the coach. It has three wires inside. Just tap the new to controller to the wires (color to color) and it will send a signal specific to that controller.
With that said, on my 2019 DS, I added a second controller to the kitchen, as Newmar had made the controller a little easier to reach, but still not in a good spot. The new controller came with a pigtail. I pulled the OEM controller, and it had a "Y" cable and spare pigtail so you could daisy chain it. I got lucky and was able to just plug the new controller in.
Don & Mary
2019 Newmar Dutch Star 4018 (Freightliner)
2019 Ford Raptor