I'm just messing around with some settings when I noticed something while rendering... there's a tiny button, almost too small to notice on the left side of the render window... it's there while you render....
You can click on it while your render is in progress and you can change some of the render settings...
Anyhow... what I was working on that has been a problem for me was using a wet skin look with tan lines, the two conflicted because both used geo-shells. Well... my main problem was using a geoshell add-on for wet skin! Now I use the tan lines add on, and just adjust the skin surface settings. I set the "Glossy Reflectivity" to "1.00" and "Glossy Roughness" to something low between "0.1" and "0.3". I was using a wet skin add on that I didn't need....
So, problem solved! I thought I would post about it anyhow... the final render with wet skin, tan lines and nothing messed up (usually in the genital area). Oh, and I also set the genital area's settings with the same glossy and roughness settings, as that is separate...