Why are you having to remove and reinstall Mach? Do you not have a XML. file of your on, something like ScMill.XML that you save and then, when you download a new version, It will ask if you want to copy custom XML. Are you going form an earlier version of Mach3? If you are going from Mach2 to Mach3, you have to enter all of your settings the first time. I would also keep a current copy of my xmls, any screen sets, grabber profiles, and Licenses files on a thumb drive or CD.
Brett