I suggest that you use a custom Route class that overrides Route.GetLinkPoint. The BarRoute class in the SequenceDiagram sample demonstrates one variation of this, although it connects to a regular node and only routes horizontally rather than vertically. You’ll need to customize it to return a point that is on the horizontal line segment between “A” and “B” that is closest to the other node (whether “C” or “D” or “E”).