You can run an installation of the agent and record your responses, placing them in a configuration file. Then you can re-use that configuration file for other agent installations. When you use the configuration file as an option to the agent installation, the installation is silent.
Record the installation by running zlm-install a r <config file path>. This creates a config file with your responses.
To play the installation on another workstation in silent mode, run zlm-install a s <config file path>. This installs the agent with the same configuration as specified in the recorded installation.