Martin go into the Mach3 folder you'll find it on C: drive. There's folder called xmlbackup. In there will be files with extension something like MachMill.xb1 or what ever the profile was you loaded before went wrong. Rename and replace the .xb1 with xml. ie: Machmill.xml.
Then copy it into the Main Mach3 folder. Now goto the Mach3 loader and it should be there ready to load.

The correct Xml file may still be in there. Just rename and load whats in there one at time and check if machine comes to life. Restart Mach each time.

If not there then we will have to reconfig your settings but first we have work out what you have. There will be more questions you'll have to answer and check for us.

Unfortunatly no plans to be down your way anytime soon. But between phone and email/pics I will get you going provided nothings broken.

Is this Computer connected to the internet.? If then I could remote into your system and take look. Would mean you installing piece of software to allow this but it's completely secure and you control what I can see.