First, I dont know if it's the same on a Mac, but on a PC these kind of errors are usually solved after a proper reboot of the computer. It's like Poser leaves bits and pieces in memory and at some point it gets too much.

If you have't tried restarting your computer (or mac or what it's called) do that. It might solve it.

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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.