Deleting the WinFileCache as suggested doesn't solve the problem for me. I've also tried forcing Dreamweaver to regenerate its Configuration folder and then re-enabling just the CSS Sculptor extension. Product versions are as follows.
CSS Menu Writer 2.0.2
CSS Sculptor 2.0.4
Site Assist Pro 1.0.6
Google Chrome 18.104.22.168 (often the default browser)
I will keep trying different things here. Any further suggestions or insights into what could be going on are welcome, of course. Thanks.