A thread discussing Tersus & version control can be found @ http://www.tersus.com/#Id=2287, and refers to recently added documentation on team modeling @ http://www.tersus.com/#Id=2309.
Import/Export of a subset of the model requires understanding of how models are maintained in the file system (this is explained in the Understanding how models are maintained in the file system section of http://www.tersus.com/#Id=2315.
In short it is possible to copy a package hierarchy via the file system (as trp files and folders) from one application to another, as long as there are NO references from any of the models in the package hierarchy to models outside the package hierarchy (a reference=a sub-element in a model). If there are any such references the target application will issue missing model exceptions and fail to run.
A partial alternative to copying specific models from one application to another is to open both in the same studio, select any model (which can even be a System or View) in the first application and Copy it, then switch to the second application and use Paste (Import) which will copy the selected model and all models of it's sub-elements which do not already exist in the target. The result of this is different from copying the package because:
Lastly, we currently debating new functionality aimed at improving application modularity, and while there are no concrete features planned immediately, I do think you should stay tuned, as it might get interesting ...
Hope I did not get you too confused.
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