This seems to be a P5 bug, I've had similar problems. Once you start getting this error it seems to re-occur everytime you to render the same pz3, so I suspect that the (pz3) file has been corrupted in some way. Are you using the same pz3 or are you reloading the figure into a new scene from a cr2? It may be worth renaming whatever files you are having trouble with then recreating them (or re-installing if it is the cr2) and seeing if you can identify any differences that maybe causing the problem. Bill