New option added to the Settings/Gcode section in LaserWeb4. Specifically Check Size laser power value has its own field. If you are using this feature with your machine please add a value for it to work. More info here
http://cncpro.co/index.php/33-documentation/initial-configuration/laserweb-configuration/14-gcode.
PS : Those values are reference only, im using a Diode Laser