Thanks for the explanation. Not sure I understand it (I thought things like Amazon VMs were almost entirely customizable and so could be configured like any local server, but you learn something new every day!
You might want to amend the documentation to either list all the unsupported cloud VMs explicitly, just say "no cloud VMs", or provide details about why some cloud VMs don't work (e.g. "Cloud VMs that do not support protocol <whatever> are not supported by DocuWare.")
Are VMs from Expedient and Rackspace supported, for example? What is the required IP protocol that is missing? Just curious...