Jeff01 I'm not a moron - honest, I promise I'm not. That's exactly what I did last time. I'm sure it is. At least, it's what I meant to do... ...however, starting with just a 4-light set I have managed to get it working exactly as you describe, even working on larger light sets (like the one I'm actually using in an animaiton now!). Last night for the first time EVER I rendered a (fairly low-res, draft) version of the animaiton out to bitmap files in one pass. Without crashes. With shadows. Cool! Many MANY thanks not only for the (VERY tedious!) workaround, but for being patient enough to slow us down and go through the motions step-by-step. It seems I CAN now render shadows and use some of SR4's positive benefits. Now - off to read my IM and that other thread... Cheers, Cliff