message to/from a subprocess
I wish to see message flows that originate or end at the elements within a subprocess, like on the attached diagram.
I realize that implementing this is a non-trivial task because Modeler doesn't allow direct manipulations with expanded subprocess - only on a separate page containing subprocess internals.
Suggestion: implement a dialog like one in BPM Suite - modeler - intergration - interprocess communications: let the user go to the properties of the originating element (e.g. message send) and then pick up the diagram, the pool and finally the element within the destination pool.
This way user will set up the message flow at the subprocess page; it won't be visible here yet the top level diagram will show it - connected to the subprocess boundary if collapsed or to the element if expanded.