program exceeds machine maximum

Hi, this is my first post outside of the Ethercat section.

I'm getting beat up by a z axis travel limitation, although I did somehow get the program to run once. My understanding of the problem is that my g54 is in the wrong spot. 

Fusion 360 says the max Z height is 0.6", so I moved my Z axis almost all the way up, then set the G54 Z position to 0.6". I did have the program run once, but then I stopped the program. When I go to re run the program I keep getting the same z axis error.

I've attached some phone pictures.

   

I have my MAX-Z-LIMIT set at 20mm & MIN-Z-LIMIT set at -255

Usually when I run a program, as I set home and stuff like that manually I'd home to a mark on the column, then bring the tool down to a height of 6.35mm above the stock, set by a pin, touch off at that height. Which sets the Z zero on the stock.