To be honest I have never used it. As the config is Wizard driven it is pretty easy to run through. :)
I believe that you can edit that file and when you run the EVConfiguration it should place the values in the config file as the defaults.
I opened it in Notepad and this is at the top of the file.
<!-- ev:service_account - enter the Vault Service Account fully-qualified username between quotes (optional) -->
<!-- ev:site_name - enter the Vault Site Name and Description between quotes (mandatory) -->
<!-- ev:vault_store - enter a Vault Store Name, Description and Location between quotes (optional) -->
<!-- Note: The Vault Store Location must exist and be accessible from the configured server -->
<!-- ev:additional_server - enter a Server Name and Domain between quotes (optional) -->
<!-- Note: The Server must exist and be accessible from the configured server -->