I'm not sure of the question here. If you've done the basic configuration as an H323 gateway by configuring your dial-peers your gateway configuration should be fairly complete. For SRST you have two options, telephony-service (CME for SRST) or callmanager-fallback. Using telephony-service provides more options than callmanager-fallback. If you have a CUCM server you would need to set the SRST reference on the device pool so that your phones know where to try and connect should the CUCM server be unavailable.
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.