Roughly speaking, diffuse+specular+ambient+reflection <= 1.  You have 1 in diffuse but with a dark (black?) color, same with ambient.  Maybe back off the specular a bit.  Set ambient value to 0.  Perhaps try setting diffuse down to 0.2 but give it a medium-light grey color.

     Try adding a figure to the scene as Phil suggested;  that will check for a bug.

     Check the normals forward box and see if it makes any difference - that will check for inconsistent geometry normals.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5