need to know ez-trak version number
some are the same as a Prototrak Plus which can take some Fanuc 6m gcode and translate it to SWI format
there is a manual called the Prototrak Plus CadCam interface manual that explains SWI gcode at least for an older 2 axis mill.
there are rules on what the machine controller can accept. in particular how arcs are coded.
i was like a lost golf ball in tall weeds until i got the CadCam interface manual then it was like a light bulb turning on. it is so simple once you know the gcode rules. If all else fails read the manual