Since yesterday afternoon, I've been unable to play any content through the NOW app on my YouView box. Don't know if it has anything to do with the rebranding update. The app loads, lets me choose content, then I get a black screen with the new green circle (rather than the coloured dots), and it goes back to the apps page of my box. Other apps like Prime are working fine. Can't view catch-up, box sets or live, so nothing at all ...
I am guessing you have tried unplugging the power to both the Youview box and Router for a minute to see if that fixes it.
The rotating green circle has now replaced the four spinning coloured dots when the NOW screen is attempting to open and load on the new NOW rebrand update.
I haven't ... hoped it might resolve itself with the box being inactive overnight. I can't just randomly switch off my router, unfortunately, since I need it to remote in to work ... I will try that during my lunch hour, though.