I can set it, and NVDA is announcing the color when I select it from the grid that's presented. I did not try the "More Colors" button.
Be aware that the first button on the "Fill" tab is "No Color" and it's always there, and first, in case you want to clear any color that you may previously have used. After you select the color you want, the "No Color" button is still there and prominently featured. Once you land on the No Color Button, you must right arrow through the first set of colors, which start with white, and when you hear white again you're in the grid where you can down/up/left/right arrow your way around. It may be easier to avoid all this altogether if you know the RGB value for the background color you wish to use. If that's the case, go directly to the "More Colors" button and activate it, then if you're not already on the custom colors tab of the More Colors dialog, navigate to it. The default color model is RGB and you can then get to the red, green, and blue edit boxes and enter the values for the background color you want, and hit OK.
But even if I used NVDA with the color selection toolbar/grid, as soon as I right arrowed off of the "No Color" button NVDA began announcing the colors and their respective RGB values, and allowing me to select the one I was currently on.
Brian - Windows 10 Home, 64-Bit, Version 1803, Build 17134
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