The Propagate Settings From This Machine button will open a pop-up that allows you to propagate settings from the current machine to other machines.  The left side of the pop up shows a list of settings that you can propagate to other machines.  Select all settings that you wish to propagate.  The right side of the pop up shows a list of machine names.  Select which machines you want to propagate settings to.  To select more than one machine, press and hold the CTRL key while selecting machines.