As the title suggests, expand the "Keyboard Settings" to allow binding to Numpad keys. Is it even possible?
With numlock off, some of the numpad keys are already binded to 87 key keyboards (7 Home, 9 Pg Up, etc.). You can remap your numpad keys to other buttons as long as it's still a 1:1 input mapping. But implementing this, if possible, would most likely take a considerable amount of time to design the UI as well for something that isn't standard on all keyboards.