I'm also integrating Guvnor with my web application and I'm experiencing the same problem you have. What you would need to do is to refresh the iframe where Guvnor is whenever you save the process. The problem is that right now, there is no way to add some kind of listener to Guvnor's save button when you are editing a process.
I will try to add this functionality into Guvnor soon.
Best Regards,