I'm having a bit of a problem trying to figure out how to change display states using the API. Could anyone point me in the direction of what I need to do? I've recorded this macro, but when I try and transfer the code to the add-in I'm developing the AddDisplayState() method no longer works.

        public void Main()
        {
            ModelDoc2 swDoc = null;
            PartDoc swPart = null;
            DrawingDoc swDrawing = null;
            AssemblyDoc swAssembly = null;
            bool boolstatus = false;
            int longstatus = 0;
            int longwarnings = 0;
            swDoc = ((ModelDoc2)(swApp.ActiveDoc));
            swDoc.ClearSelection2(true);
            boolstatus = swDoc.Extension.SelectByID2("My Component.SLDPRT", "COMPONENT", 0, 0, 0, false, 0, null, 0);
            Configuration myConfiguration = null;
            myConfiguration = ((Configuration)(swDoc.GetConfigurationByName("Default")));
            boolstatus = myConfiguration.ApplyDisplayState("Hook");
        }

Any suggestions?