Sorry, I've got no other pics. It is hard to see detail, now that you mention it. I can see a chain wheel at the top frame but I don't see the chain or rear sprocket. I see another chain wheel at the bottom frame and what looks like a chain and rear sprocket but no connection with the rider's pedals topside. I also spy what looks like a seventh wheel: small, white and on left side - it may be a stabilizer, sort of a single trainer wheel. How does this thing get pedaled? Maybe it just coasts?
I think there is a chain running down to that crankset in the middle, and then a chain running from the left of that to the left hand side of the crankset at the bottom, which then drives the bottom wheel on the right. So all the friction stuff is really just for show... Oh well.