Hello!
Your answers on this survey will help guide the development of Macintosh software for making virtual Lego models. This exciting area is known as LDraw, and was made popular by the LDraw program for DOS and many other programs since. (See www.ldraw.org for more about that.)
There are two free LDraw programs now available on Mac OS:
Both of them are still what you would call Beta software. I'm the guy working on them and I wrote this survey to get feedback on what people want.