Ok, thank for you help.

light settings are:

 

Shadow Blur Radius
Shadows Samples
Shadows Min Bias

you mean Shadows Min Bias ?

 

Ok, i do some tests and i'll post again some renders.

 

thank.

Poser Pro 2014 SR 1 on Windows 7 64 bit
I use IDL, Gamma Correction and EZSkin for all final renders.