This document goes over the setup of NGiNX in a Windows environment and as a Windows service, and the implementation of CA Process Automation as a cluster using NGiNX.
There is a new and updated version of this document on CA Support Online as a knowledge document here:
http://www.ca.com/us/support/ca-support-online/product-content/knowledgebase-articles/tec1324121.aspx
The major change is the new easier way to create a service.