The validation settings in the CSS Form builder wizard are applied to the Server Validation errors, not to the spry elements.
I will log a bug to look into why the spry validation is not included in the css settings.
After applying the form builder wizard and setting the Form Actions settings, a Universal Email server behavior is added to the page.
If you wish to make changes to the universal email settings, you do so in the Universal Email server behavior not through the form builder wizard.