Ok, here's the relevant code:

In lua.rc:
LuaDir "$ConfigDir$lua\"
*LuaFile "$luaDir$lua.lua"

In theme.rc:
include "$ConfigDir$lua.rc"
*NetLoadModule lslua-0.4.3.1 load lslua.dll "" LUA Scripting

Let me know if there's anything else that you need.

Thanks