@ronillon thank you for quoting me. I follow with great interest!
Sorry, but I didn't understand how to assign a key to a controller. I am making a custom one, and unfortunately it doesn't recognise the button input of the controller (set as a joystic button). I could do it via the interface program, though it would cost me to remap all those buttons that would already have the same Keybinds... I would like to ask you if you know of any keys that are not used by KSP.
I'm still curious how to do it with a gamepad (I have an Xbox 360 controller).