Then there are 3 possibilities:
1. the controller is defective
2. you did not download the DirectX redistributables as indicated on the plugin page
3. the installation was damaged. You have to back it out and reinstall it
If you have not downloaded and installed the DirectX, then I would do that first. After that I would remove and reinstall the plugin. Here is a link on how to do it:http://groups.yahoo.com/group/mach1mach2cnc/message/132662
If you have a way to test the controller or replace it with another one then you could try that last. After these steps, if the problem still exists, you can send me the XML file and I'll look at it.
Keep me posted.