The original graph was intended to ‘make masses’ for the users to play with. Optimization for space planning is quite a bit different; there are several examples on the forum, the Dynamo blog, other blogs, user blogs, conferences, the generative design primer, and even in the old Refinery sample graphs (sadly lost to time, but it was up for six years).
The good news is most (all?) of those examples don’t use lunchbox. Since the topic is somewhat unrelated to the original (an implementation of another tool) I recommend starting a new topic with your progress on a generative method of your choice.