You're using an old VSS prop with an old Template_Skin shader. It's best to download the PR3 prop (with updated shaders) from bb's site. All the adjustment parameters are lined up down the left side of the shader, so it's much easier to use.

You could try adding some tint using the tint colour.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)