We talked about using SVN and the Moodle community use of CVS, here's a suggestion for how you might use SVN with CVS synching in from the community repository
An intro to Roles and capabilities in Moodle with links off to more detail. These need to be considered and honored when building an interface to the Moodle system
Project announced in April that provides for online marking of PDFs for Moodle19 returning the marked item to the assignment activity. Uses Ghostscript to generate PDFs and Javascript in the client to markup the PDFs