Maybe give this a try. May be a kludge - but might get the job done.
Open MS Paint
Pick a number - say 8. Pick a font, Say Engravers - or what ever you like.
Type the number - save as a monochrome BMP.
Import the BMP into MACH2, USE the Spiral cut - It will start at the lower left, but then drive to the middle of the number and cut in a spiral. If you figure out on a "test pass" where that is (the center), then you could set up a jig on the worktop to hold the pieces in the same place for the other 11 numbers.
As I said a kludge - but works around learning all that Gcode and re-reading the MACH2 manual! Jim