After chatting with the Apple guy, and I didn't believe him either, I cloned my internal HD to the empty partition on my external HD. Then I ran the Install Mac OS Sierra app that I downloaded and it upgraded that partition to Sierra without problem.
Not the way I wanted to do it but it will do and so far the couple of apps I was unsure of seem to work just fine but I will use them for a day or two just to make sure before I clone that partition to my internal HD.
