I made this mesh last year as I am learning to use Wings 3D, and was going to release it as a freebie. However I was not happy with it, and shelved it until i could figure out what was happening and how to fix it.

I made the mesh in Wings, UV mapped it, and textured it, but it seems whenever I render it out in any version of poser P4, P5 or P6 I always end up with this horrible mess of horizontal banding lines visable on the semicircular part, and on the mesh
I used what I thought was a reasonable number of sections in the semicircle parts of the mesh, but it still looks like this.

Any ideas on how to possibly salvage this?
Thanks