Hi Abe.
We don't have hills that steep in Vegas however, I have not seen the motor turning off in Sport. Here is a video I took of going up a hill in my neighborhood in sport, pedaling as hard as I could. In parts of the hill, the power bar did turn red for a second or so, but the power output never reduced. Now this was only a 100ft climb at a max 6% grade.
As far as the second issue that has not happened to mine. and I leave it in my garage, turned on overnight, and never have an issue like you are describing.
That being said my ST7 turned into a brick today due to the pinon not working. Soooo that is new. (see my post from today).
I hope you get these issues resolved. -J