Hyperion does work in Mixed OS mode. For Web applications deployment, you must deploy all of them to either Windows or Linux.
On page 151, its about HFM. If you have HFM as source for FR or Web analysis reports, you should install & config HFM, FR/WebAnalysis on Windows creating new domain of Weblogic.
If you dont have HFM in your deployment, you need not worry.
It all depends if the planning applications are going to be in classic mode, if so then EPMA is not required but if you want them to be managed by EPMA then it needs to be installed.