Hello,

That could happen if two boxes are very close. The algorithm searches for a path in a grid whose squares are marked as occupied when an Obstacle box intersects them. That could lead to some free space between two boxes marked as occupied if the RoutingOption.GridSize is larger than half the distance between the box borders. To fix that, set smaller RoutingOptions.GridSize - however this will make routing work slower.

A similar problem could happen if the routing algorithm decides that a path lying exactly at the box borders is less expensive than a path where arrows go farther from the box. Increasing the NodeVicinityCost should fix that.

Arrows should not overlap if there is enough space between boxes, measured in number of grid squares. Decreasing the routing grid size should help here too.

You could handle the ArrowRouted event and check where the found path satisfies your criteria. If it doesn't, you might assign new coordinates to Arrow.ControlPoints.

I hope that helps,
Stoyan