Genome Prototype on Hold, Spiral Island for XNA

I'm putting development of Genome Protoype for XNA on hold for a little while. Now that the actual beta for XNA Community Games is underway, I've noticed a lot of the downloads on there are very small in size.  Based on this, I've decided I'm going to drop back to the basics, and go back to the original 2D version of Spiral Island g, as a challenge to see how much I can push into the currently 150 MB filesize limit and see if I can fit the whole thing.