Right now when you toggle, either the blocks are there, or it's full of air. Instead, I'd like two different states. For a simple example, toggle an area between lava and ice.

Are you sure? It seems unrelated to me. Unless I'm misunderstanding something, and this change allows me to do what I wanted?

Now that I think about it...Perhaps having two separate toggle area signs would accomplish what I want. Sign 1 toggles the lava, sign 2 toggles the ice, and now that they are redstone controllable, i can combine with an inverter to make a single lever select between the two toggle areas

.... >.>
Sorry about that. That was directed at Assembla, and apparently Github accepts the same syntax...

Added. Fourth line is other state, use "-" to do nothing on off state (use in tandem with several toggle areas).