I am using Protege 4 on a mac running OS X. Protege launches OK. When I attempt to load the owl file for our Cardiovascular EP ontology (owl file is local) I get the message "The system couldn't load the ontology http://protege.stanford.edu/plugins/owl/dc/protege-dc.owl". Then protege requests and answer to "resolve?". My response appears to cause Protege to hang. Any ideas what might be wrong?