the Access points for Design Extender extensions are in the webAssist menu.
What other extensions are installed?
some may have the access points in the Insert -> WebAssist menu
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.