That's a very cool build - talk about involved. I saw a video of the original somewhere. Some serious $$ went into it for sure. You may have noticed mine is anything but an authentic reproduction. It's something like "old steam meets new mad science".
It's a lot safer and simpler, actually, doesn't even have a fire box or containment boiler. Interesting that they are running it at 200psi. I'd like to do that, but I see that the standard at steam meets is to limit psi to 100. I imagine they have a good reason for doing that, so that's what the pop-off on mine is set to. Besides, that as much pressure as my water pump can handle.