Thanks for you response. Returning it to the dealership next Tuesday.
Dealership kept the car overnight and had me pick it up mid-afternoon of the second day.
They told me they had a TSB 19-2031 (I can't find it on the internet). It was about removing the driveline and lubricated the flange with "special grease."
Then they introduced me to "The 10 Speed Transmission" guy/expert. He said he deleted all prior information in the tranny computer. He then reprogrammed it. He told me it is an adaptive tranny; therefore, he drove the car many miles to "retrain" the memory bank. In the diagnostics he could see I was not coming to a complete stop when the car was in reverse before putting it into Drive and I had several episodes of not coming to a "complete" stop before accelerating again. According to him, this causes issues with the computer which can result in the rough down-shifts I was experiencing along with the clanking noise when it shifted. He advised me it will take a week or so to fully retrain the tranny to my driving style.
He also told me that if I ever have a question or want him to ride in the car for me to not even call the dealership for an appointment just come in and ask for him!
So far, the few times I've driven the car all is good!
I thank everyone who posted a reply to my thread.