First off, let me share who I am and what Xbox One I own. I live in Luxembourg, a country where Xbox Live has never been supported and most likely never will due to its small population. My Live profile is bound to the UK marketplace after I migrated it after long years of struggling with support from the German marketplace.
I bought a Day One Edition from Amazon.de, so, in essence, I own an imported Xbox One. All services on the one are tied to your profile. So if your profile is tied to the UK marketplace, you will see ads, movie recommendations, application recommendations, etc, for the UK marketplace. If you are tied to the Norwegian marketplace than the worst thing that could happen is that the feed supplying this information is not available. Should you have your profile tied to a different region, like me, than everything is just fine except for the occasional content that is region locked (although no Xbox One content is to date to my knowledge, speaking from experience with the 360) and you may need to go through a VPN to get it.
So all in all, I see no problem with importing an Xbox One. The console should work just fine and if it is officially launched in Norway, I am pretty sure it will just start loading all the content from the Norwegian marketplace if your account is tied to it. The reason why the console was not released was market focus and console saturation, not some technical issues. They simply wanted to flood their major markets with consoles.
I say, go for it. You will anyway have a warranty and right to return the goods if you purchase online, will you not? I am a bit fishy about the Norwegian law. I think that things are looking pretty good and that if you want it, you should get it.
Update
Since I have posted this, I have run into some problems. It seems that payment methods are subjected to more scrutiny than before the One was released. Even purchasing on the 360 has become less forgiving. For example, using PayPal to make a purchase on a UK account while residing in Luxembourg has resulted in a payment block after three failed attempts. I had to contact the advocacy team to get it unlocked. Furthermore, they seem not very understanding of the problem and just scold you for trying to make purchases out of region.
However, using a gift card to charge money onto my account seemed to work just fine. It seems like that is the method I will have to use. Unfortunately, this might mean that I can't benefit from several services such as video streaming as they, to my knowledge, require an active payment method on your account.
As by the Xbox.com page on how to configure your audio settings, the One does support 5.1 just fine via HDMI.
But although your Xbox One supports it, your Home Theatre does not. RCA is a dated technology that is not able to transfer the data necessary for Dolby 5.1 as RCA only supports two channels (as in Stereo). Depending on the device producing the audio, it might try to approximate Dolby 5.1 but it will only ever be an approximation.
Best Answer
You are actually able to turn the Xbox One off. If you hold down the home button, and choose turn off console, as long as the white light on the power box is on, so is your Xbox. Downloads will continue.