There is no limitation as far as inside or outside phones apart from the total number listed by max-ephones under telephony-service. Just that remote phones (outside phones) can register and send calls only at g711. g729 is not supported. Because of which Cisco TAC does not support this configuration.
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.