That's really well done; I wish I had that in the program I'm working on. I ended up traversing my data structure and making a graphviz file, then doing it again after the manipulation I was testing in order to verify that it worked correctly. That works, but it really doesn't scale very well. Plus, the being able to see the individual steps of the algorithm would make it much more clear and obvious.

As an example, http://db48x.net/reposurgeon/pathmap-diagrams/generated-path... is one of the graphs I generated.

Have you published the server and the protocol anywhere? I'd use it even though I would have to write the client side myself. For my project it would even be desirable to write the client side twice; I'm porting a program from one language to another, and it would be amazing to be able to compare the implementations visually.