Genesis 8.1 only renders with grey skin - what am I doing wrong?

Hi all,
I have purcahsed a few 8.1 characters, but they all load with just a plain light grey skin. If I loan the 8.0 version of the character they render fine.
Has anyone experoienced this and if so, how do I fix it?
Thanks!
Comments
Most likely you are still usign an older version of Daz Studio - the PBR Skin shader used by many of the Genesis 8.1 characters requires Daz Studio 4.15 or later.
Thank you. I will try this