I'm guessing that box.lua (and what it requires) is the asymmetric encryption algorithm, but where is the documentation?
It uses an unusual set of jargon, doesn't say how it should be used, and doesn't say anything about itself.
From what I can gather, it's hardcoded to generate 256 bit keys; so unless this blows RSA out of the water in terms of efficiency, it's either going to be too insecure to protect the small amount of sensitive data or too slow to protect the large amount of less-sensitive data.