You need whatever dial-peers you need for inbound and outbound communications to that office while in SRST mode. MGCP doesn't use dial-peers since it gets its dial-plan from CallManager.
If CCM is not available, SRST takes over and uses the dial-peers configured on the router. SO you will need to configure your outbound local, long distance, international, 911, etc dial-peers and your inbound dial-peers.
Depending on the complexity of your site and dial-plan, you may need translation rules, adding an auto-attendant TCL script, the vm-integration so calls forwarded to centralized voicemail system use the PSTN, etc.
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.