Could somebody suggest what may be the problem with the attached render whereby you can make out what looks like a hatch pattern on the left side of the dress. It doesn't show in preview, only when rendered. I have tried turning polygon smoothing on and off but it renders the same. As this is my first attempt at modelling, I am curious to find out whether it is a Poser problem or a problem with the model. The dress is Dynamic not conforming. Thanks in advance.

It looks like a problem with shadows intersecting with multiple lights, and I don't know the proper fix for it - I try to avoid it by positioning the light, but I know there's a better way.  Pretty sure it's not a problem with your model.