Lua is a popular choice amongst game developers due to it being very easy to intergrate, fairly fast and there's a big user base (because it's so popular)

But since the API exposed to LUA in any given game will be different, there's no compatibility reasons to use it.

If you're dead set on LUA then I'll see what I can do to help but I would personally recommend you use Rem objects Pascal Script (https://github.com/remobjects/pascalscript) or Delphi Web Script (http://code.google.com/p/dwscript/ - I think there's a 'newer' fork floating around somewhere) or indeed there are a handful of different scripting engines written by people here, I can't remember who but somebody was working on a full ECMAScript (javascript) engine for scripting.

Point is that the projects I mentioned are native to pascal and as a result it's far more convenient (and portable) to use than wrapping up a C lib.

Plus it's not like LUA is the *fastest* I wouldn't be suprised if PascalScript could beat it on performance in more than a few areas.