Touching up LifeMaster Eggshell is like touching up the mattes that are popular now, i.e. Aura. Here's how I do it. I take a little bit of paint and add a few drops of water - just a few. Mix well to thin the paint. Then I dampen a small sponge brush and use to to apply thin coats. Horizontal and vertical - not all the same direction. It dries fast because the coats are thin. Better to do multiple thin coats on the spot than one or two thick.

No matter what finish, even flat, if the light hits it right, you'll see it. Doing multiple directions can help diffuse and hide.

Good luck with everything - glad you have your color.