Custom routing for link

i want the link to display link this example Org Chart Editor
but i use graphLinkModel, i tried go.link.Normal ,go.link.orthonal,avoidNodes for the linktemplate
Flowchart
in the example of flowchart , you see ,if the node is rectangle, and three node links to the node , the node will have three ports for connection, what can i do if i want the rectangle node act like the start node , it links to 3 nodes but only from 1 port , if tried to change the shape of start to rectangle, it acts right , why the step node can’t act like this,if i change the category to empty, the start will act wrong

I’m sorry, but I do not understand the situation and what you want. Could you include some small screenshots that illustrate what you have and what you want?