To be honest with you, I'd throw that hunk of junk away and get a 708c. It is way easier to use and doesn't need a dongle for software and features are still being added. I had a leetro 6515, 608 and a 708c. The 708c is by far the best I've used. The conversion from the 6515 to the 708c took about an hour to wire and tune. It was that easy!
http://www.glenspeymillworks.com Techno LC4896 - 2.2Kw Water Cooled Spindle | Moving Table Mill from Omis 3 CMM, 500Lb granite base | Epilog Legend 32 Laser Engraver