Are you sure a Lua interpreter is the way to go? I was pretty smitten with Lua at first — even started writing a book about Lua development (in the Codea environment) for kids — but the deeper I got into it, the more it annoyed me. I’m afraid that romance turned sour rather quickly.
So I ended up developing MiniScript instead. See the discussion thread here, or try the demo. I believe the code is quite solid; I’m mostly working on fleshing out the docs before I submit it to the Asset Store, where it will be a paid asset. However, if you want to incorporate it into your game now, you can have it free as an early adopter (plus getting lots of personal support!). Just PM me if you’re interested.
well, I’ve scorched google for days (I skipped this and work on other features in the mean time) and found LUA. I’m so new at this I don’t even know what this sort of functionality is called - what I’m supposed to google.