Farming Tour/ Harvestfarm problem

[Hagbard]

I am new to the game and these addons so I don't know if its an app problem or user error. I am trying to use the HarvestFarm tp create a farming route . I have a lot of nodes on the map but when I hit the calculate tour button it replies "was not able to calculate a good route with given minimum route length" . Am I missing a step ?