I'm trying to get this demo working on an extremely inexpensive plain VPS (running Debian 7), and I'm getting "WebSocket connection to... failed: Invalid frame header". Is that what you saw when you as a result of hitting the 40-50 client limit? I am getting the error on a first connection, so it's probably something different.
I'm going to answer my own question - I tracked it down to a bug in lattice-core that occurred when it couldn't parse incoming JSON, and for some reason it killed the socket server. I fixed it by rescue the JSON parse and all is good now.
