If one activity is the behavior of more than one call behavior action on the activity diagrams of the use case activities then the "create behavior view" function reacts unpredictably: sometimes it will confuse the different calls behaviors. Sometimes it will even throw an exception.
looking at the code I can see why this would happen, I'm not sure how to fix it yet ...
https://community.nomagic.com/reassign-copypasted-flows-to-copypasted-callbehavioractions-t4742.html