It works in Chocapic13's, Sildur's, BSL, Conquest of the Sun, Edi's,.... Only Kuda seems to override it. It's the first thing I notice when I try any shader.Smooth lightning is probably not in effect in any shader. Else it would interfere with the shader.
I think I figured out what the problem is. It's not the "smooth lighting" but the "od lighting" under shader options. For some shaders and even different versions it must be set to "on" or "default" and for some "off". I think for Kuda it must be set to "on".Indeed, but it must be incorporated properly. Some shaders use different lighting.