How to remap M5 $0 in Plasmac?

Hi, 
I understand that M3 and M5 commands are typically used for spindle control. However, in Plasmac, these commands have been remapped. For instance, M5 $0 is now used to stop the plasma cutting tool.
During the process of stopping the plasma cutting, certain events are indicated by M5 $0.

Could you kindly direct me to the file responsible for this remapping? This will allow me to customize the sequence of events according to my requirements.

Best regards