I figured out the problem, if you launch it without setting your ram limit to higher than what it default sets it to, it will not let you play or make a world. Append this to your JVM arguments so that it doesn't do this again:
What this does is set the max memory allocation to 1 gig instead of the 0.25 it was set to before. I hope this helps anyone else who runs into this annoying yet easy to solve problem.
Edit: Apart from that annoying bug, it's a great tech demo, I'd love to see how it goes.