To start, stop and configure the firewall to automatically start on boot up go to the Guardian Digital WebTool main page and place the cursor over "Services" in the title bar. Click on "Service Configuration". To start the firewall manually click on the red text "Stopped" on the "shorewall" line in the "Current State" column. Once the firewall starts the red text will change to green text that says "Running". To stop the firewall click on the green "Running" and the firewall will be returned to the "Stopped" state. To enable the firewall to start on boot up click on the red "Disabled" in the "Boot State" column and the text will change to a green "Enabled". The firewall will now start on boot up. To disable this click on the "Enabled" and the text will turn to a red "Disabled" and the firewall will not automatically start on boot up.
When first experimenting with any new configuration you should seriously consider a couple of things. One, until you have a configuration that is proven to let you into the firewall either by the Guardian Digital WebTool or SSH you may not want to have the firewall starting on boot up. It's no fun when you've accidentally locked your self out of your firewall.
The second consideration is that you should have console access in the event that you do lock yourself out. Configuring a firewall from a remote location is risky business.