I'm having a very frustrating problem.  I've been modelling an old fashioned shaving kit in Blender and today finished the meshes.  Everything went well and it renders fine in Blender.  I scaled things down to a size appropriate for Poser figures and exported as an OBJ file.  I then switched over to Poser 6, imported the obj files at their default size (not percent of figure size) placed on floor.  Everything seemed fine.  I applied the MAT files in Poser I'd set up, including some textures I'd made, so far so good.  I then did a render and got a strange result.  The prop's shadows are square boxes, and the prop itself is black as if in shadows.  For the life of me I cannot figure out what is causing this and I'm at my wit's end with it.

My only clues are as follows.  If I scale the object back up some it renders okay.  It doesn't seem to matter if I do this in Poser or Blender, either before or after exporting.

If I go to my lights and set them all to raytracing, the prop again renders normally.  If I turn on depth shadows on just one light, that light throws a boxy shadow

If I add a larger prop or figure, it seems to render normally.

Any help would be appreciated, I'd like to start making props again but right now Blender is pretty much all I can use to make them and if I can't sort out what's causing this I may be stuck.  It seems to have something to do with scaling the problem but I'm not sure why that cause the problem.

Here are a couple of images of the Shaving Brush showing what I mean.