UI questions and comments for the new sequence diagram:
1) Issue 131669
2) Why is the cursor a cross hair for resizing a synchronous message and a up/down arrow for resizing a lifeline?
3) It is hard to select message to self when the lifeline is already selected.
4) Should RE operation should generate "joined" action box like 6.1?
5) How to manually join and split action boxes?
6) How do I reverse the order of two messages?
Remaining questions transferred to UMLRadar.