Is there an option during a Windows agent silent install to set the "Download configuration file from management server on startup"?
You can use /CENTRALCONFIG or /LOCALCONFIG to set this (defaults to /LOCALCONFIG).
We use "/VERYSILENT /DIR="C:\Program Files\NetXMS" /CENTRALCONFIG /SERVER=hostname_of_netxms_server /NOSUBAGENT=winperf" to do a completely blank install, and then serve the config from the server.
Peter