Communication languages between the client and OOUI kit.
Relationship service from CORBAservices
The application establishes interfaces in the ORB for the classes in the model. It can do that with whatever method pleases it, e.g. IDL files or the dynamic stub interface.
It also establishes interfaces for the relations in the model, following the specs of the CosRelationsship (basically letting the interfaces inherit from some base classes, e.g. Role and Relationsship).
UML UI diagram exported as XMI. Transfered to the kit by a client library.
UML UI diagram exported as XMI and transfered to Kit seems like a confortable way to store (parts of) OOUI definitions. A client library can read the XMI data and transfer it to the kit via the normal corba interface.
However, I'm not sure, XML makes sense here at all. The app has to expose the app data to the kit and propably needs interfaces for this anyway. There's no point in creating the model via XML, if it is already there.
But it may makes sense during the development process: From the UML UI diagram, code for the corba interface and its implementations could be created, which the devloper then only has to modify.