When you Poser -> File -> Save, ALL the Octane information (rendertarget and materials) get saved to the pz3 file. When you File -> Open, they will all be reloaded. If this is not happening, then either you are opening the pz3 by doubleclicking the file icon in Explorer (which the FAQ and Manual both indicate will not work), or your python installation is corrupt, and you should be able to fix this by reinstalling the latest Poser 2014 SR.I just saved a render target real quick and it appears it only saves the data from the rendertarget tree (which makes sense). So unless it's hidden in some fancy way, it does not save material setups
Paul