https://issues.jboss.org/browse/JBPM-3412 has been resolved and fix will be available in the next release jBPM Web Designer version scheduled next week. In the meantime I have pushed the fix to http://people.redhat.com/tsurdilo/oryx/latest/ for you to test it (this is _not_ an official release!). Let me know if you still run into any issues regarding JBPM-3412 with it.
Thanks.