I don't agree about the RAM causing CTRL-Z probs (or rather I DO agree, but it's certainly not the only reason CTRL-Z messes up.) I reckon it's also down to bad queueing of undo operations (one starts before the other finishes). I try never to use CTRL-Z at all, but if I accidently press it twice on more complex scenes Bryce will usually crash. I've had it crash with a single press, when it tried to undo before it had completed the operation in the first place. The reason I'm saying it can't always be memory is that I have 1Gb of RAM - so how much d'ya need??? ;)))) All the bugs I've found (main ones are soft shadows / CTRL - Z / focus / light gels / volumetric artefacts) not only happen in Bryce 5.0 and 5.01 but also in Win98 and XP. But I've never used Bryce on anything else, though, so I'm sure there are platform-related differences, especially between PC & Mac.