I think my issues was not a Yosemite problem but just one of those Mac things.
I ran permission repair and it found no problems. I ran a few tests of my own and found that I could save to my Desktop but not the internal HD. I opened the Permissions list and saw only System, Wheel and Everyone. I, the Admin, was not listed. I added Admin to the Permission list for both read and write and so far that has fixed the problem.