Activate=1 means TRUE i.e. it IS working (or supposed to)...
Device= means whatever ".device" is to control it...
Unit=2 means that it is the 2nd LOGICAL device on that controller (device) i.e. the one with its SCSI ID set at 2 on the little wheel/piano arrangement that identifies it in that SCSI chain.
Oh, and I take it that they are all tooltypes in the icon, what does it say in the DOSDriver file itself?
(P.S. I am currently 3 sheets to the wind on Drambuie, so maybe you should rely on somebody else's advice.)
