Looks quite possible yes. The question is who will do it? Why not simply start with the script on the site you mentioned. You have to change the directory from .tomboy to .conboy and install the dependencies. Mainly graphviz and xsltproc and it should work.

Then you could use something like the command execution widget to put it on your homescreen or create an .app file that runs the script. To me it looks like there wouldn't be a big benefit of really integrating it into Conboy. Instead, leave it as external tool.