Safedisk does indeed use a blacklist, but , and this is a big but…where does it store the info on your drive? How do I know, well I successfully backed up Generals zero hour using alcohol. Clone Cd was installed on my drive, but the game played no problems, that is until I started to get the dreaded ~DF394B.TMP errors. At some point I enabled the ccd tray, only to be met with please insert the correct CD. Eventually I found the .tmp errors were from a corrupted hard drive, I uninstalled/reinstalled Generals zero hour only to face the please insert the correct cd. The only soltion was to uninstall CCD, and immediately after a reboot, my copy worked.
So by enabling my hide cd tray and attempting to play this game, caused safedisk to blacklist CCD, stored that info somewhere on my hard drive, because after uninstalling/reinstalling with a clean registry using fixit utilities in between, I was only able to play by uninstalling clone CD.
If we know where safedisk is storing this info it may help many people!!