When you say no shadows do, how do you mean, is it that there are no shadows for instance cast from a person onto a prop? I work in C4D and you use a compositing tag to stop certain things form rendering but still casting shadows. That said you could always just invent your own shadows on characters by doing a selection of a copy of a person for instance and filling it with black, then doing a distort to drag it onto the ground, then reducing it’s opacity to make it more grey. That is a very rushed synopsis and there are a lot of mags out there and books that would help you along better than I could.

I there are no shadow on the character render form poser have you enabled shadows in the rendering settings. Over in the poser forum you’d probably get people more familiar with poser output.