I've made a single activity that I'm using as a classifier behavior for a block. Within that activity I have an activity diagram in which I'm using swimlanes. To fit the swimlanes from each of the parts of the top level block I have broken the swimlinanes into 2 separate rows.

Now if I make a new activity diagram under the same activity, I can right click the diagram and then display inner elements. This automatically brings in all of the previously created swimlanes in a single line row.

Q1: Is there a way to split up swimlanes once they've been created? I don't want to create duplicate swimlanes in the containment tree.

(I know that I can just copy the previous diagram and the swimlanes are broken up the same way as before but this doesn't quite solve my problem)

Additional questions: 

Q2: Why can't I drag existing swimlanes from the containment tree to a diagram within the same activity?

Q3: Why when I click display inner elements doesn't a menu appear that allows me to select the specific elements that I want to add?

Q4: How do I get a swimlane to show the actions that have been already allocated to the part property that the swimlane represents