I don't have most of these problems. Cancel has worked for me so far and I've used multiple figures with multiple hires materials and some of those were done with a very complex node structure. I can switch runtimes in a matter of seconds. I've actually seen more "out out memory" errors in ProPack - not once on P5/P6. I'm not sure about the Magnet thing. Do you mean a second magnet comes in as Mag 1? I've had that happen a couple of times but I renamed it to Mag 2 and it has saved and reloaded fine. I think that user experiences vary quite a bit from individual to individual. I've had Materials not show up in the library when going to the material room but show up when I refresh the libary. I've also seen a couple of times where I did a render and then went back to the preview window and nothing is there - but this is Opengl related. Going back render options dialog and back sets it right.

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