I already have a custom color on a particular face and it is not part of my palette. How can I copy that particular color to another face and or the palette for future use?
If you have SW14 ...
2014 SOLIDWORKS Help - Copying and Pasting Appearances
2014 SOLIDWORKS Help - Determining the RGB Components of a Color
2014 SOLIDWORKS Help - Color and Appearance of Parts
If the color was assigned to a face, right click on the face that is the color you want. Select the Color Ball. Select the level (Face) that is giving it the color you want. Now pick other faces; they should change to the same color. If you pick a wrong face, just pick again to return it to its previous color.
If the color was assigned to a feature, then I think it will assign the color to features as you pick them, not faces. Probably the same for bodies or parts.
Retrieving data ...