Nancy! I have got the exact same problem! Jason, please take this problem public and not in private since I guess there's a lot of people out there having this problem!?
Me too thought the CSS sculpture extension looked promising but it really needs to be looked over and rebuilt from scratch! As it is now its almost more hazzle than help for someone who does know CSS but needs to create layouts faster. For someone who does not know anything about code it must be a nightmare!?
Ive got it to work by disable the preview under webassist preferences in dreamweaver but that is not how its supposed to be? The preview works in my other extensions without java script errors. Turning it on and off when changing extensions is not very convenient!
I will follow the threads carefully what happens in the process of solving this issue!