Now I have identified the problem (bug)! When only the SA extension is installed the unique db value option is available in the Server Validation Behaviour. I uninstalled everything and even DW itself. Then installed only SA and built a standard wizard set. The unique value validation for the email field is applied as set in the wizard interface. When I then install the CSS Form Builder extension and try out my SA built set nothing works. The unique value for the email field in the registration page is gone! I have then tried to delete all pages with SA and FB still installed and tried to build a new set from SA wizard. Same problem, unique value for email is not applied even if set in wizard interface! There seem to be a lot of compability problems with these 2 extensions (SA and FB)!?