How do I fix the hairline? The image in CC4 everything looks good. In Unity there is a noticeable coloration difference around the hairline. Thank you.

Not a Unity user, but what you see could be the skull cap, which has a separate material. Check the Opacity.

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Ok thank you. That put me on the right track. Unchecking 'Preserve specular light' for the scalp_Transparency material did the trick.