OK, I think I have the workflow... create pose in Poser and morph brush till the heart is content.  Save scene with just V4 if you want to use a Carrara scene.  I have used the Global Illumination scene and modified it in Carrara.  I would open the V4 scene with my posed and morphed V4 and it seemed to carry the morph brush morphs over (clicking the carry moprh option in the dialogue box upon opening scene in Carrara helps).  Then in the browser tray bring in your Global Illumination scene, scale it up or scale V4 down...and there you go.

Thanks,
Philip