Wow. That's a lot to digest at the moment. I did change some of the formatting in the headers in Git a couple weeks ago to make the headers easier to parse with a regex to extract all the function prototypes. Maybe some of the changes I made will be beneficial to you. Send me a pull request if there are additional formatting changes you want me to consider.
Anyway, very cool! I've been eyeing LuaJIT for a while, it seems pretty neat. I keep bouncing back and forth between that and Chibi Scheme for what I want to use to script my next desktop game. LuaJIT is faster and possibly easier to set up the FFI stuff, but Scheme is just such a cool language.
Again, very cool. If you get a project set up for it somewhere I can link to you from the Chipmunk website.