In addition to the connectivity provided by a topological network, it also enables you to set directional restrictions on Links, and turning restrictions on Nodes.
In the example above the road named Leafy Lane is to be designated a one-way street, preventing entry to it from Main Street. Select the Link item representing Leafy Lane and click the right mouse button to display the local menu:
You will see a prompt in the status bar: Enter position on Link item near end
Click near the end of Leafy Lane near Main Street. This will display the Connection Type dialog, where you can set the connection to In, Out, Both or None.
Select In to indicate that the direction of travel is “in” to the nearest Node, i.e. the junction with Main Street.
Any route-finding performed on the network will obey these directional limitations.
The junction of Acacia Road and High Street is to be designated “no right turn” when travelling from Acacia Road. Both Acacia Road and High Street remain bi-directional; it is the junction which has the restriction, so it is the Node which will have the limitation placed upon it.
Select the Node and click the right mouse button to display the local menu. Select the 
Junction… option:
A Junction Details dialog is displayed showing a diagram of the junction. The three “option buttons” enable you to select one of the three roads leading into the Node.
Click the option button representing Acacia Road, then click the square indicating the southward portion of High Street. This will prevent travel from Acacia Road southward into High Street, but does not restrict travel southward on High Street generally.
When setting turning restrictions in this way, there can be unintended consequences. Firstly, it is possible to accidentally restrict a turning, making it impossible to travel to one or more parts of the network. Secondly, it is possible to inadvertently force a route in an unacceptable way.
The example of “no right turn” from Acacia Road causes both of these problems. The first is trivial: it appears impossible to access Diagon Alley from Acacia Road. This is simply because the example only uses part of a real network. In practise there would be further roads which would lead to Diagon Alley without travelling south on High Street. The second problem is an unintended consequence. Travelling out of Acacia Road the route is forced to turn left. To access Diagon Alley it is possible to travel to the junction with Snake Avenue, perform a U-turn, then travel south on High Street to reach Diagon Alley. In a real road network this would be undesirable, so it is necessary to edit Nodes to prevent U-turns.
Display the Junction Details of the Node at Snake Avenue. Select each road link in turn and disable the ability to return down the same Link:
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