There is a readme in the .zip.
-- Installing the Plugin
Copy the Network.csx files into your Construct/PLugins and Construct/Plugins/Runtime directories. If you have any issues with this asked somebody in chat.
On the first layout add the Network plugin object and make it Global. You don't need to add the plugin to any future layouts. --
That means, put the "network.csx + the runtime folder" in the "Plugins" folder.