I think we have a terminology problem here!
I see the ActiveX component as a subset of the object model. When you use it, you also use a small number of objects which are only used with ActiveX (and not in an add-in such as MileCharter, or a "stand alone" such as GridImp). However, I'm using the term "object model" to refer to the full group of COM objects.
I think you should be able to just change or remove the version number. Try it!
Richard