Error starting flowable-rest: ProcessEngineFactoryBean cannot be cast to ProcessEngine

Found a solution here: Flowable-custom-context.xm is too bad as configuration sample!
But didn’t work for me.

Also tried this: How to configure flowable-rest.war using JNDI
But no luck.

Ummm… am I missing something major? Why is it so hard to start the REST service with the default (supplied) config?