Mach3 is not free. What you had previous was a pirated copy of Mach3 that gave you more than 25 lines. IMHO Mach3 is a nice product but way too expensive for the casual hobbyist. Add to that, the fact you need to run XP, I looked elsewhere. I chose linuxcnc. It is a bit difficult to set up if you aren't familar with linux but after that, very easy to use.Linuxcnc is free. They do have an install that installs linux and linux cnc the makes your job a bit easier.
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