Infinite Loop Detected
The initial code to build the world never finished running. It’s probably either really slow or has an infinite loop. Or there might be a bug. You can either try running this code again or reset the code to the default state. If that doesn’t fix it, please let us know.
Aha, one more change from the CoffeeScript compiler that I had missed. (Wonder how long I’ll keep finding these…) I’m deploying a new version now; should be ready in 20 minutes, after which another browser cache clear will help.
Sorry about that; thanks for tracking that one down!