Ken, have you upgraded to the XP version of Mill Professional yet? This is not to be confused with the upgrade to Mill Expert.
I am not aware if there is a charge for this "straight across upgrade" or not, but it would hopefully put us all into a similar code base.
Anyway, check in your NC setup and see if there is an option under coordinates for scaling. I know XPert has this, but I don't have the older Mill Professional on here any more, but I am pretty certain it had the same sort of provision.