I am working on a pretty powerful engine that might become a "game development" engine, but it is accessed using BVM script (which is almost just like bb code), but you don't get the source.
Yeah, me too. The set of functions of my engine looks a lot like Quake3, and there are scripts to define materials, character animation, paths, etc. "Code" scripts (the one that define tha game logic) are done with BVM. "Definition" scripts (those that set properties for materials, etc) use the standard .ini format.