I'd like to help test this as well. P5 with Athlon 2000, 512 ram, running XP. I have a question about shadows. From the interface pics, it looks like shadow value, map size, etc. are the same throughout all the lights. Will we be able to disperse shadows across the lights, ie-every other light, or like in your new cluster feature, say turn on shadows for only clusters, or only non-cluster lights? This does look like quite an interesting program. How about a couple rendered images, one with your lights, and one with a more standard light set?