Hey, love this board even though it's cheap and has quirks.
Through trial and error and scraping what little info's on the internet I've been compiling a list of all the functions the keyboard has into a reference sheet:
https://docs.google.com/document/d/1Xcz-icfTZxGKhU3agoq8VXxt0K008tbxyg4y1-HZHGw/edit?usp=sharing
I know it's late, but I hope this helps someone get more usage out of theirs.