PR's OAF Editor has been tested to work with the demo of Descent 3, but hasn't been tested with the full version, as it is not out at time of writing. The OAF file format can change for the full version of Descent 3, and therefore PR's OAF Editor may not work. If this happens, I would no doubt make an effort to release another version that would work with the full version of Descent 3, so check the Packafied Web Page for latest updates.