Still working my way thru special pen plotter app based on acro 1010. Set everything up per videos. x limit sw on left side of X axis. Y limit sw at front right corner. Loaded pre set "acro 1010" in Grbl settings in Control software. X Direction switch in settings is set to reverse direction. X Gantry moves to the left (in the direction of x lim sw) with manual "-X" jog. Gantry moves forward with manual "-Y" jog. Able to set and successfully search to a new marked zero point within the XY frame. Machine successfully traces a counter clockwise rectangle with the "check size" button. Machine moves in a clockwise path for a single test gcode polygon in work space. All good so far - I think. But when I press "Home All" machine screws up. X gantry goes right instead of left in the +X direction, away from the X limit switch and bangs into the right side, tearing at the timing belt if I don't stop it in time. Why?