SW2015.  I have an assembly that has a cut on it.  I changed to the color of that surface and everything looks good.  However, as soon as I regen or reopen the part or do some other command the color disappears.  When I select the surface and select Appearance I can see the color is there in the property manager.  If I accept it the color comes back, but as soon as I regen it it disappears again.  What am I doing wrong?