What is the underlying BPM workflow engine that the outsystems platform V7 and V8 uses? Is it jBPM and what version or Oracle 11g?  Please advise.  Thanks
Hi Brian and welcome to our community!

It's the OutSystems workflow engine.
Check out the Business Processes and Workflow section on help.outsystems.com.
And to know more about the lifecycle of activities check out http://www.outsystems.com/help/servicestudio/8.0/Designing_Processes/Process_Activities_Life_Cycle.htm