OK, then uninstall Poser Pro 2014 (application only, leave the content alone). When re-installing the application, the installer should offer you to 'Use existing preferences'. If you choose that option, all your external content runtimes should remain linked as they are now. You can then install SR1 again.

Before you uninstall, could you render an image that shows the artifacts clearly, and then render the exact same image in SR1? It would be very helpful to see a side by side comparison.