Well kharrisonkevin, thats about all the trouble shooting i can offer. I do not know the Mach software (have a back round using/running commercial cnc controls ), but with the g53 and g28's working the same ("wrong") i would guess its something with how the home position is set up, which is why ive asked if you have run any other gcode programs.
Hopefully with the info you have provided, someone with a Mach background will be able to help you.
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