[Chimera-users] Collaboratory

Dear Chimeramasters and mistresses, I'm having some serious difficulty starting a collaboratory session in UCSF Chimera on Mac. I have tried both an outdated version (build 40427) and the latest (build 41367). I can't find any mention within the program of collaboratory, and because of the Mac OS I don't think it's possible to start a hub from outside Chimera. Is there an additional extension that needs to be downloaded and installed seperately? Yours studiously, Theo