For those of you who have fallen back to the s version and want to get their previously saved in t scene back: The following seems to do the trick:
First of all load the scene in Poser and save the lights and the camera (just in case, and keep a back of the scene)
Now in re-install the s version (be sure to copy the octane.dat file as well and have the access.orp back in the temp folder (copy them in both locations)
Now start Poser again from fresh
Delete all from the default scene (no lights, no andy)
Start the plugin
Then do a File Import Poser scene and load your scene.
In the plugin do a Re-Import the whole scene just incase something was left
Now the lights should still be ok, if not load from the library again, same for cameras
Then refresh from the plugin
If you have saved the octane material in the Poser material, you probably need to remove them in Poser: Select the figure or prop and in the material room use the Remove Detached Nodes on each of the props and figures you have saved the octane material in.
Obviously you have lost the Octane material settings, but they were corrupt anyway
Hope this helps
Configuration: Windows 10 64bit Creators Edition, I7 6850K, 128GB, 2 GeForce 1080ti, P11 Pro SR6