I developed a fairly comprehensive demo based on this blog posting:
https://community.jboss.org/people/bpmn2user/blog/2011/09/21/jbpm5-web-example
Also look at:
https://community.jboss.org/thread/177691?tstart=0
where there is a WAR that has been modified to support jBPM5.2. If possible you should use the WAR attached to the last posting.
Hope this helps!
--JE