You will want to install cyberGFX v4.12 right from the upgrade disk/archive. No need to install from cd first.
http://aminet.net/package/biz/patch/cgxv42_r1
You will loose modes due to conflict with os2.9 exec.device
Then you can update to v42 rc6 which will correct the issue. (dont do a first install from this update)
http://powerup.amigaworld.de/download.php?id=9