Currently (i.e. version 2.3) we support up to 500 locations. They would be configured fully meshed. Generally, the portion of the config containing the network locations is identical in all CUEs, the only difference is the one line which tells it which location the local one is.
Currently the only one that's officially supported is Unity, although I believe networking to Avaya's Interchange works OK, too. If there's demand for that, contact your account team. Most of all it's a matter of being tested thoroughly to make sure everyone adhere's to the standard the same way.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.