If there are lines in your program that need to be skipped over sometimes, add the forward slash character "/" the beginning of each line you may want to skip.
The entire program will run normally unless you press the "/" key at the Auto Mode screen; then only lines not marked with "/" will run. The marked lines will be skipped over. Suppose there is a point in the program where you might want to occasionally check the part:
some code
.
.
/m09 (set coolant off)
/m00 (stop program)
.
.
.
.
.
/m09 (set coolant off)
/m00 (stop program)
.
.
.