To change between Celsius and Fahrenheit go to Settings -> Appearance -> International and select your location under "Region".
Not at all obvious, is it? I think this one sets the correct time zone as well.
I added my NAS SMB folder by adding a location like this: "smb://192.168.2.21/music". This lets me browse all my music in the alphabetical subdirectories.
Something similar should probably work for you, but you may want to create a public shared folder on your PC if you can't get it to work directly.
Obviously, you should also change the IP address to match your PC. I tried to use the name "NAS", which is how every other device sees it,
but I couldn't get that to work, so I just used the IP address.