*this link is to their Kansas City, KS location which I've never been to, but it gives you an idea of how it all works. I couldn't find a webpage for the KC, MO location in the Crown Center.
proof that we really did eat there before (11/06)
a few shots from this time
(note: The top left corner is Buddy's interpretation of putting your fist in your mouth and the top right corner is a shot I caught of Princess Sparkely mid-sneeze. She thinks it's hilarious. The bottom, center picture shows an empty restaurant... we were there at 5 PM on a Thursday night, last time we went it was packed and there was a line outside to get in.)
The food isn't great. But the price isn't high either. The milkshakes are pretty good, but aren't brought by train. Don't go expecting a great meal, you're there for the train.
Plus, here's some other family's video of the train bringing the food to your table.