When the Instance Tool is activated (i.e., when the Instance Tool Button is pressed), a menu appears with the list of networks that can be instantiated in the currently selected network. (Note that only networks loaded into the HUGIN Graphical User Interface tool can appear in the list.) However, if there is only one network that can be instantiated, no menu will appear. If you select one of the networks in the menu, you can now place an Instance node in the Network Pane: Simply click the left mouse button somewhere within the Network Pane. When you have placed the instance node, the select tool is normally activated again. However, if you want to keep the Instance Tool activated (to create a series of nodes) hold down the SHIFT key while placing a node.