I never had this problem with PPP, but in P6 it doesn't seem to matter where I place the lights, I always get a shadow from an upfront object, if there's one there, as if the light were facing head-on down the Z axis. I can put all the lights down the Z axis pointing even behind the object, and still I get that shadow - from the front. I have the SP 2 installed, too. Is that a bug, am I missing something obvious? Or has Poser 6 created its own new laws of physics without telling me?

If your talking about the preview, then those are "Ground Shadows", they can be turned off from the Display menu.

If that's not it, please post a screenshot or render.

3 things to bear in mind... Poser 6 gets its knickers in a twist with Pre-P6 light sets. You can save them out from P6 then re-load them, which seems to help. That also worked in P5. Poser 6 doesn't really like more than 6 infinite lights (although most of my light sets use 7 or more and work ok). OpenGL doesn't preview more than 8 lights correctly.

Poser 6 gets its knickers in a twist with Pre-P6 light sets. I bet that's it, really, because I did exactly that: opened in P6 and subsequently saved my preferred, custom-made PPP lights as default. That never would have occurred to me. Thanks. :)