in the example you present a opb diagram (operational process) but i did not find how to produce it with capella 0.8. subsidiary question : how to produce operational processes (activities chains)?
To create an Operational Process (it is the same for Functional Chains), you just have to select several Op. Interactions in an OAIB or OAB, then right-click and a contextual menu appears: Operational Process -> Create an Operational Process.
Then a blue square appears, named OperationalProcess1. You can edit its name, and then to modify the OP you need to create a contextual diagram. Right-click on the square symbol: New -> Operational Process description. In this new contextual diagram, you can now edit the OP (remove / add new involvements).