Thank you very much for your help. I think I got what you wanted to explain. Because Superfly renders "real" raytracing, the false weave reflection is making some other results. you are totally right about gamma setting, the checkmark is on settings and not on the other one where I can set 1.

I have to work now, but I started to tinker a new material. actually I wanted to make a glitter material based on a blender tutorial but it didn't came out as I wished.. inadvertently I made a discovery with this cycles shader and it looked nearly like the iridescent material I was looking for 😅 So I will post it after work, to show you the result. It renders in all variations of superfly.. 

So I don't have glitter yet... but now I have a good iridescent base 😅