I don't have an answer to your questions, but I have seen a number of posts from people not happy with the Nav system. Plus at $125 to $150 for a map update, you are much better off going with a Garmin or something similar.
I don't think you can, I have a 2015 XLE and thought I had the higher end radio (entune, navigation and such) called the help line to set it up and he said my Vin didn't have it. I asked if I could upgrade and add that stuff and he said no
Issues here too. The system works fine with my iPhone and BT. I plugged the phone into the USB port and it wouldn't play through USB. I shut the car off and turned it back on and the phone would play music then through USB. Then I switched to back to BT without unplugging the phone from USB. It played fine through BT with the phone still plugged in. Then I switched back to USB and it would not play unless I turn the car off and back on.
So I plugged my ipod into USB and it would not play. So I turned the car off and back on. It locked my ipod up solid. I had to bring it in and sync it.