Hi,

You could use Graphics members such as DrawString and DrawLine to draw text and arrowheads. If you only need thicker lines, you might try setting a larger DiagramLink.Pen.Width instead of custom-drawing.

I hope that helps,
Stoyan

What I suggested was to add/subtract res from points 1&2: you should have the X coordinates of points 1&2 different than the X coordinates of points 0&3 in order to change the arrowhead angles.

Now if you also need to pull the link ends apart, that should be based not only on their height, but also on the number of link incident to a node. You can divide the node's width by the number of links to find the point positions, then set the incoming link ends to the left-most points and the outgoing links to the right-most point. If you sort each group by the links' height, the links won't overlap.

I hope that helps,
Stoyan