Cascade Dropdown fails in 2013-01 and 2013-02a if the fields involved in the dropdown are specified as Required fields. The workaround is make the fields not required. The code fails to be able to locate the fields in the DOM and set the Select type if the field is required -- search by Title fails as when a field is required in SharePoint 2013 the field Title is set to "This Field is required".
Comments: Also see: https://spservices.codeplex.com/workitem/10224
Comments: Also see: https://spservices.codeplex.com/workitem/10224