Thanks for your feedback, ronstuff. I wasn't sure whether the effect was reproducible until you commented. You're certainly correct in saying that the problem involves the naming of lights. In this DNA set, as I'm sure you've already discovered, a simple renaming of LiGHT1, LIGHT2, and LIGHT3 eliminates the freeze! Thanks for putting more light on this issue! I've been a bit slow in replying having spent much of today trying to gleam some understanding of the subtle differences in saved light sets. At the very least, I've now learnt how to get Poser to save a set of lights with the PointAtParam listed before the translate/rotate stuff or after it! I've also learnt that it doesn't make a jot of difference! What I was trying to do was to generate a freezeable light set from within Poser 5, but after many conjectures and no refutations, I've (at least for the moment) concluded that sometimes you can't see the wood for the trees! As a simple renaming cures this particular freeze, then I'm beginning to conclude "if it ain't broke, don't fix it". Maybe a very simple solution for widespread render problems in Poser 5 is indeed lurking somewhere!