From what I can gather it seems to be a simple GPIO interface - they have instructions for specific OS's here but mention that it's "unsupported due to the inability to modify the system in LibreElec".
That... doesn't sound right to me, and I get the feeling it was more that they didn't want to bother figuring out how to do it themselves.
So has anybody else used this or something similar and figured it out? I've done quite a bit of googling and can't really find anything specific to this board.
Thanks in advance.