Couple questions about your configuration, we can get you an updated DOS program possibly but I need to know:
Are you running this directly from DOS? You will not be able to operate it properly if you're attempting to run a command prompt window from inside Windows.
There is a file called pcservo.cfg in the directory where the application is located. If you can get the file off of there and send it to us we can modify it for you and get your scale factor set to the correct one.
Let us know the version of DOS being used and make certain your running natively in DOS not in Windows.
Christopher @Techno Inc. CNC Router Systems
Tech Services Department (http://technorouters.com/help TechnoWiki)