Has Creo 11 updated the VBAPI (Interop.pfcls.dll), or does it still support VBAPI code from Creo 4?

I’m currently using Creo 4 to test interference detection through VBAPI in C#. When I try to run the same code in Creo 11, the application launches and the working directory is set successfully, but I receive a 'pfcExceptions::XToolkitInvalidName' error at the line session.OpenFile(modelDesc1).Activate();
 

One more question: Does Creo 11 support rotating and zooming the assembly to capture the interference location?