Thanks very much, Deb. I'll go ahead and make a few small changes then. The merger/redirect is certainly useful. 

Thank you for your offer of help. We do have a few things that need fixed which are beyond our technical skills! One anomaly is that the operetta categories are independent of the opera ones although operetta is supposed to be a genre of opera. It may be simple to bring the operetta branch back into the opera tree. I'd be grateful if you have any ideas! Best