Hi mfris,
your question about "shared interface" is more general and principal. When you make a one model from another model, it creates dependency between "pieces of solutions" with only one direction from "using" to "used", where one is "client", second is "source". It is the same, as relation between components in SW, but here, in models, it is on more abstract level. In another words, if you make a replication from one model to another model or distribution by XML, you make the same process, as in component technology (for instance in "your COM") "compiling components, adding reference, linking components". You make not anything as "shared global interface in COM". See the process of distribution or replication only as technique how to link models as physical pieces of solutions from source to client. Answer to your question is: Make replications between models with this view on it (models are compound from components of models, replication is linking). If you are developing the source, you must recompile it = "re-replicate" it...
Jumbik.