Recently I was at a customer site that had the requirement that all products that live on Linux had to be installed using scripts. No GUI installs were allowed in their IT shop.
Many Linux(Unix) customers will not allow Xwindows to be run in their IT shop. In these cases the WebSphere Infrastructure Team will need to use silent install scripts to build the assorted IBM BPM 8.5 environments. Here is a link to a doc that I wrote for a customer. This document will help the reader complete the IBM BPM 8.5 Advanced install process.