Z3TA+ 2 was not bundled with Platinum. It was sold separately. If the plug-in is installed make sure "Z3TA+ 2_64.dll" or "Z3TA+ 2_64.vst3" is in the CbB VST scan path. If the plug-in is in the scan path, check the plug-in manager to see if the plug-in got excluded. If it is excluded, run a VST reset or temporarily enable "Rescan Failed Plug-ins" and run a regular scan from preferences.