Main Core runs on its own for now.

I updated Main Core to run on its own since I ended up not uploading
some cores it relied on. Will need to uncomment some lines when we start
integrating the relevant cores. Next up, I'm getting what I think is a
recent copy of rendering core and committing that change, then I'll work
on integrating it. If you have a newer copy ready, feel free to
overwrite the version I end up uploading next.