David,

if a BPMN construct is missing in the modeler, you are very welcome to enter a bug here:
http://bugs.eclipse.org
Choose the STP project, the SOA product, and the BPMN component.

Note that the BPMN modeler is only about BPMN. No BPEL transformation bugs will be accepted there.

There is a fine line between modelling and then transforming the process for execution, and have a direct approach where you build an executable process. We have chosen the best compromise between modelling and executability and we will try to improve on that going forward.

Thanks,

Antoine