Sorry for the time I took to reply and thank you all for the information provided, the post process solution did worked out, no more white artefact, yet since it is a dirty trick and i'm not too fond of dirty tricks I prefered to understand the problem and fix it inside the material. So I broke the links 1 by 1 until I…
Ah ok I see, I was using it wrongly then, since i was using it to boost the diffuse color. Everyday is a school day, thx a bunch everyone problem solved and more knowledge acquired thankx to all of you :P
Diffuse power is kinda like the smoothness of the transition between lit and not lit areas of the surface. The higher the power, the smoother the transition will be, but the surface is not "lit" as much if it's not directly not facing the light source. As far as I know, it's just (L.N)^DiffusePower. You don't need to use…