Hi,
Just for the sake of it, I tried doing a manual installation directly from the p2 repositories. I started with downloading the Neon.3 C/C++ package. Then I added all the needed repositories, i.e. the same list as in the Oomph setup file. Made sure to only have those enabled. Then I installed all the features, selecting "All Available Sites“ so I could install all features at once. Selected the same features as in the Oomph setup file apart from CDT and EGit since they were already part of the package.
After installation everything worked as expected. I could switch to the Papyrus perspective and I could switch to the UML-RT viewpoint. Creating a capsule with a statemachine also created the diagrams as expected. So from what I can tell this all works as expected.
I think we are back to the fact that we have no good instructions. So I really don't know what you did that made it not work. As Charles wrote, we will have expert users running into the same issues as you did Ernesto.
To be honest though, I don't understand how anyone would like to go through this when you use an Oomph setup file instead... ;-)
/Peter Cigéhn