BBC World News from New Broadcasting House

There was also a time during Mandela's passing, they used a darker orange colour to blend in with the sunset images on the screens. I think Newsday uses a brighter shade of yellow.

I would assume they can get just about any colour they want on those light boxes by controlling the primary colour lightbulbs?

Yes almost any colour is obtainable. They're led strips of red, green and blue throughout the set so it's just a case of programming the lighting desk to call up the right colours. World Business Report used blue, Newsday is yellow as you say. The studio is also used for HARDtalk and The Film Review both with further lighting styles.
I thought that all studios at NBH have similar flexibility, though there are limitations in E because of the real newsroom view (there are fewer LED elements visible on screen) and A where almost nothing actually exists! Studio D was lit in some very bold colours for the World Cup when it was used for a world Service language programme (can't remember which one though, might have been a BBC Mundo one...)

I'm not sure about the technical reason behind them looking that colour when turned off, but those lightboxes certainly aren't permanently red when switched on.

ISTR seeing black sky scrapers on the light bar in front of the desk in E during Dateline London

Think BBC Persian did a show in D - with some AR - for the World Cup.

I don't think it's a lightbar, it believe it's LED - hence why the image is changeable to the graphics for Dateline London, and there is a also a little bit of animation on the red image that's normally used from what I've seen.

I remember an insider saying on this forum that they had ordered the wrong bar, and instead got a LED one, like they have now, then the one that World has.

I thought it was the other way round. E got the right one, and another studio got just a lightbox.

I thought it was the one hanging in the newsroom, as seen during the TOTH camera pan? Wasn't it originally supposed to scroll the news headlines or top story?

The newsroom and studio E hoop screens are indeed lower res than originally expected AFAIK.

Whether this was down to a cost factor or just a poor spec I don't know.

The LED screen in E will have cost significantly more than the LED lightbox in C. Nobody would have mistakenly ordered one when they meant to buy the other.

No but I believe the perceived resolution of the screen was lower than expected so became less of a feature than planned and not adopted at all in studio C.