Epilogue.
Shortly after sending a letter to the CEO of Ritz-Carlton, I received an email from the manager of The Portman Ritz-Carlton, Shanghai and a further apology. In addition, I was told that all charges have been rebated, they have addressed the issues raised in my letter and that they look forward to my visiting the property again for a much better experience.
I look forward to visiting Shanghai again and to a much better stay there, as I am sure (and hope) my experiences were an aberration.