Kristy,
Yes they are sitting.
BUT, I am going to have to make new ones. I normally use Sculpty, but it was so hard I couldn't shape it. I used the Sculpty Ultra Light which is real light weight, so the fake eggs are not as heavy as they should be. Mousebirds will shimmy to turn the eggs, and when the Widower shimmy's he shimmies the fake egg out from under him. Plan be on eggs is to take one already made and use it as a model for an RTV rubber mold. Then I can cast the egg in plastic, which will have the right weight. These type of eggs then will be the density of the eggs that are sold commercially for chronic layers.
Since the blue-naped liked feathers to put in their nest I gave the white-backs some. They went right down and snagged them up. Hopefully another pair will go to nest in the colony.