I do not know how to describe, but Poser dynamic hair do not fit to skin. It looks nice, most of your renders looks pretty, but hair and skin looks like made with 2 different software and are affected by different lightsets. Carrara hairs are more suitable to skin shaders.

As BagginsBill wrote, I think the main reason is "hair" shader node. I do not understand all nodes in very advanced materials, but in hair nodes I do not understand even simply math function. I do not know how light can affect edges only.