M68 E0 Q0  (set minimum laser power to 0)
M68 E1 Q100 (set maximum laser power to 100)

G64 

G0 X0
F1000
M68 E2 Q100 (set commanded power to 100)
G1 X5
G1 X6
G1 X7
M68 E2 Q50
G1 X8
M68 E2 Q0
G1 X9
G1 X10 M67 E2 Q50
G1 X15 M67 E2 Q25
G1 X20 M67 E2 Q10
G1 X22
G1 X25 M67 E2 Q100
M2