John made a suggestion to do the test laser and line up zero that way. It works well on my CNC Laser, but the CNC Router isn’t so repeatable, especially with a larger bit.
I actually found a separate program CNCCam “http://www.c21systems.com/CNCCam/” It does the crosshair overlay. I have tried to purchase a license but they don’t reply. When the nag screen pops up drag it off screen or it will pop up again.
On my CNC Router I use an endoscope camera 3 meter cable $12 Tmart.com. It works Great! Have a Macro setup to home and set offsets to match camera to Origin. Then I can fine tune the crosshair line up. It is very accurate, down to about .01mm. Then I Have a Macro to Set X and Y to Zero with the offset between the camera and actual tool position. Then I have a Prob Z Macro that does a touch off. From there I just hit Send and off it goes. Perfectly repeatable each time.