The Process Automation product wikis contain a document about installing and upgrading multi-product stacks. In particular, this document lists several installation and upgrade scenarios with different combinations of products and middleware. Each scenario lists the recommended installation order for a multi-product stack, and provides any workarounds needed to complete the installation. This document is meant to supplement the normal install documentation that is delivered with each product.
Review this document before you install or upgrade an environment that contains multiple process automation engine products. You will find this document in the Installing and Upgrading section of each product's wiki. For your convenience, here is a link to the document on the CCMDB wiki. Note that all of the Process Automation product wikis link to this same document.