The Roku Channel is only currently available in the US and Canada at this time, only available on Samsung TVs in the US. If you are located in any other region, this is likely why that article isn't loading properly. If you are located outside the US, this would explain why you aren't seeing the channel available on your Samsung TV.
Would you have another link? When I click on the one you posted it says: "Article not found. Please check the url and try again."
The link worked for me. Also, when I viewed the link I noticed this line:
The Roku Channel can be added to Samsung TVs running Tizen operating system version 2.3, 2.4, 3.0, or 4.0.
So, check the OS version that you are running. Now, the NU series is fairly recent, so it most likely has the correct firmware. I have an NU7100, but honestly have no desire to run any apps on the TV itself. In fact, I have two different Samsung Smart TVs (JU7100 & the NU7100), along with a couple of Vizio sets, and I don't use the smart apps on any of them. I vastly prefer using a Roku or Shield for my streaming platform. Samsung just has too many limitations in what they offer.
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