Update: there were lots of broken things, they're now not as broken. The number of grey boxes has increased a little. And as it runs, it pushes to the address bar, which means you can share and save your creations. Let me know if it doesn't work, as I'm always a little afraid when I'm writing callbacks between AS and JS.
I guess the point of the game is figuring out how it works, so I don't want to say too much. Which is actually super frustrating, as I totally want to blab all over and spoil it.
I totally need to stop working on this now, as I have more important things to be doing. But I can't resist tinkering. The next idea that's bugging me is to add sound to it...
And if anyone creates anything interesting, please post it!