Instead of layering jpg's then how about png's? they are - or can be of better quality than jpg's AND they support transperancy. Furthermore it's a free format and afaik most paint proggies support it. .psd's are huge files, as you know and I would hate to download such a bugger "just" to get a skin texture :o)

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.