Dreamweaver wont populate the selector name unless you set the "Choose a Contextual Selector Type for your CSS Rule" option to tag.
see attached screen shot
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.