I just finished it up and it will be delivered during lunch break.
The material is Staron instead of the Corian. It was the color/pattern that was chosen by the client. The same for the color-fill.
I delivered it to the client and they are planning to use it tonight for a family BBQ.
They said it looks better than the rendering, and they really like it.
It doesn't require anything to seal or protect the fill. It's a permanent acrylic product intended for color fill.
After the polishing, I always use a nail brush and dish detergent to remove the residue, and I haven't had any of the fills show any effects.