You can manage servers and workstations from one EAE. The endpoint protection plus suite is a collection of endpoint protection licenses. If you have seperated keys for that then you can contact your reseller to create one key for use in the EAE product.

The EAE product will be installed one 1 server and from there you can deploy all the avast client installations to the servers and the workstations that need the avast software (and i know this, because i am using it like that right now).

Editting the admin.ini is only needed in special cases. The EAE controls most of the settings already from the console itself without manually editting the admin.ini