The Stand Alone version of Form Builder is not compatible with DW CS6. Either continue using form builder in the previous Dreamweaver version you had been using, or you will need to upgrade to Data Bridge in order to use Form Builder in DW CS6.
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.