Follow this blog by bpmn2user: https://community.jboss.org/people/bpmn2user/blog/2011/09/21/jbpm5-web-example
Here you will find the steps needed to deploy a web application using jBPM5.1 on Tomcat6.
Little changes to this example are needed for jBPM5.2, here is the porting: https://community.jboss.org/thread/177691?tstart=0
Good luck.