@jfbeute is right: you may even keep both Poser versions running at the same time. The test I did has been created in P12, saved, and then reloaded by P11, while P12 was still running. I reloaded the mats from within P11 just to be sure, but I didn't save the scene using P11. Just keep in mind: only one Poser computing at the same time. So that you can still use the scripts you need from P11, save either in a scene or in one of the shared libraries and then used in P12.

𝒫𝒽𝓎𝓁

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