Often opensource frameworks lack documentation, but in this case, it is in paragraph 4 of chapter 1.... http://docs.jboss.com/jbpm/v4/userguide/html_single/#d0e39
and there is even info on the 'engine' page: http://www.jboss.org/jbpm/engine.html
So I hope this answers your question and many to come.
I saw those sections but I did not see where it gives installation or usage instructions in a standalone application - not using jboss or tomcat.
Can you point me to something of this nature?
That is chapter 2, it is not literally what you need, but I assume you are clever enough to check the lib dir of the distribution and notice the jbpm.jar on a higher level, etc.... It's 'just' a java framework, nothing special.