The temp files generated while rendering, (with names like: "poserTemp.-1152986521") contain the shadowmap info and are normally deleted, automatically, at the competition of the render. If you lock-up & crash out of Poser during a render they may not be automatically deleted, even at the end of the next successfully completed render (P4), so must be removed manually. You guys that have never seen them are lucky, but you can catch a glimpse of them by viewing the contents of Poser's root directory during a render with shadows. Unfortunately, keeping these deleted has not stopped Poser's memory problem for me. ...but, then, none of the zillions of suggested remedies has ever proved to be a consistant solution. (Its sunspots man, I tell you its sunspots.)