Bouncing Balls

Well, I was able to get some balls to show up on the Q*Bert grid and start bouncing down the cubes. In fact, I cranked up the drop frequency so that they fell almost every frame - it looked a little bit like water flowing. After that, though, I throttled back on the balls and let them come in multiple colors:

They now come in red, green and purple (not shown).

Next up - collisions with the balls and Q*Bert, followed by spawning other critters.