hm good luck then
after reading this technical note, i think that by reducing the size of the lua core, you also lose the ability to parse scripts, thus you have to feed it precompiled bytecode, eh? that would render the concept of "scripts" kind of useless. correct me if i'm wrong.
you are more than welcome to try to implement this
but maybe you can invest some time & brains into coding a editing function that uses the camera keyboard before?
this way one would not have to rely on a computer to write one's scripts on. makes in-camera-debugging way easier and subsequently the use of ubasic.
whatever you do, have fun while doing it and let us know what you are up to