Not all games require writing, but some do, and prototyping most certainly does, especially in the early stages. Here's how GGS will handle that.
Also, I'm also aware that the context-sensitive menu is growing quite large. Really, there are two modes that it needs to cover - the controls you need for building a game, and the controls you need for actual play. Perhaps there should be some sort of "Build/Play" mode switch at the top of the table? Maybe something similar to the little panel that appears to let us select the marker color?