Expand child process for a call activity in the visual editor

I have been fooling around with the modeler and am trying out the call activity.

I create the child element first and name it.
I then create the parent that calls the child.

The image presented on the overall process view page on http://localhost:8080/flowable-modeler/#/processes
shows the parent calling the child element with the '+' on the call activity. However if I click into the parent process visual editor, the call activity just looks like every other task. I am not able to expand it to see the child contents. I would have to back out and look at the child separately.

Stems from a forum posting:

http://forum.flowable.org/t/flowable-ui-getting-started/205/3

Reproduce el problema en el editor visual de procesos de Flowable Modeler creando un elemento hijo y una call activity padre. Compara la vista general del proceso, que muestra un marcador de signo más, con el editor padre, y rastrea cómo se renderiza y se abre la call activity. Se considera terminado cuando el editor padre permite a los usuarios expandir la call activity y ver el contenido del elemento hijo.

Escrito por el modelo de indexación a partir del texto del issue.