Well, I've finally figured out the whoel route-finding thing. An example of routing (by itself) can be found here:
people.emich.edu/jkeswick/IS449/project/routeform.html
There are still a couple of bugs to work out in integrating with the rest of the project, but it should be ready to go very soon. This is the last of the major features I'm working on (since I got the date thing managed), so I'll work on the diagram(s) for the presentation as soon as that's done.