I got it working by messing about with p96 and PVS using trial and error.
What an unintuitive system that is, but at least I have a OctaMED screen in slightly higher resolution than normal with no flicker. Just hope i dont damage my monitor with the bizarre settings im using.
I know nothing.
I have been down this road with the exact same equipment and OSS. To get OSS to work smoothly and not to use the planar switch, I found that I would not use P96 or CybercrapX. I just use the driver VillageTronic provided.
Then I could get it to work great. I'll try to add more later...