I just noticed, though I've been using AA6Pro for quite a while... that in my user Preferences folder that I not only have a com.adobe.Acrobart.Pro6.0.plist preference file, but also a com.adobe.Acrobat.Pro.plist preference file (I also have the Acrobat folder of preferences in the Preference folder; the com.adobe.acrobat.full.plist [for AA5] and com.adobe.Reader6.0.plist for the AR app... so I'm sure the one in question is not 'owned' by them.)

Is this com.adobe.Acrobat.Pro.plist also necessary?

Is it the Acrobat Distiller preference for 6?