I've never actually used it myself, but from what I can tell it has a list of different lego parts and all the blocks are pretty much already built. I think you can even put together build sequences etc.

The spitfire came to a grinding holt after my ATI card and Maya had a falling out I now have a new Graphics Card so hopefully some more updates this week.

My son just saw your Lego and asked if he could use the program you're using

Regards
Paul