wondeering if somebody might be able to assist me.

I am running Adobe CS3 Premium 10.0.1 on a Mac, have installed
AcrCallibrator 1.2 and everytime I run the script I get the aove
message.

Any suggestions as the results I get vary every time I run the script.

Doesn't it let you continue in Unsupported mode?  Or are you taking about another sort of error?

Until Tom adds the current versions of ACR to the script's versions it knows about, ACR will say this, and you have to be careful to set things to the zero--Recovery, Fill Light, Clarity, Vibrance, etc, and set the Curve to Linear instead of Medium Contrast.