Keyboard description Larkbook X

I bought a Larkbook X .
What I’ve searched for and doesn’t found ; a description of the keyboard for the spezial keys.
when I press FN+ESC another LED is on, but I doesn’t know what this key is making ?
And could I also change or add a funktion when I press any other key (normal, or with FN or …) ?
Hope anyone can help me
Bruno Windisch