I am setting up a CNC 6040z-4s mill and the controls for the Z-axis stepper motor are reversed.  I went to the config->system hotkeys and selected page up for the Z++ and page down for the Z-- and they are reversed from what they should be.  I can reverse the hot keys assignments by selecting page down for Z++ and page up for Z-- but I am wondering if that is the correct way to correct this.  Is there some other method that this should be corrected.  Thank you.