I took two packages, one for my requirements and the other for my particular feature which I am designing. When I select "all" for the design elements, I got classes, activities, and even the actions along with their pins! I selected "all" because I wanted to trace my design to requirements. However, when I saw that many of my action pins were called "object", it became difficult to sort things out. Of course, the UML standard defines "object", so it's not something I want to change.
I then thought I'd link Activities, classes, and interfaces only, and leave anything below that out of the traceability. That however forces me to create separate Traceability Matrix artifacts. Now I suppose I could create a MatrixSpecification for my interfaces, another for my classes, another for my activities and that's it. In my report, the three tables would be output. However, my tables would then have missing entries in requirements that are covered later in the interfaces or activities table. What's a good level of granularity for tracing?