Looks like he was using the extra ring as a chainguard, the chain certainly could not shift to that with the half-plate bolted to it. Just take all that off and it should be fine.
Unless there's a spacer behind the guard, then you've got I really high top end onthat puppy. Will the FD lift the chain onto it?
If it functions as a Chainring, that's a pretty cool mod indeed. I wonder what the 1/2 guard was for? Maybe to keep the chain from jumping clean off the other side?