preplaning trips using exploroz app

Sometimes when planning a trip using the app. the app will provide a selection of ways to go from one spot to another. I have not found a way to change the selection to a way I want to use. EG going from Cameron Corner to Lyndhurst the way suggested was the long way round through Broken Hill etc. I want to go down the Strzelecki track but not an option. How can this be changed to do it. I finished up putting in a second town to make it do it there must be a way to do it. i could not find in the manual.