Does the laserboard support min & max power, or only max power?

Probably a weird question, So I’ll elaborate…
I found this site where you can define & generate lightburn test files: https://www.o2creative.co.nz/laser/

One of the input parameters is a question: Does your controller support Min and Max Power setting or Max Power only…

Which should I pick for my K40 Cohesion3D LaserBoard?

the board with lightburn software has full control over the laser power output via PWM. However you really still need to have a manual control to set the absolute max power output from the laser PSU to the laser tube to prolong it’s life. This is done via a rotary pot wired into the PSU’s 5V reference signal, so you can set the max output to about 17-18mAh(which can be read by an analog ammeter)

But as far as digital control goes, yes the board can control it. It’s all in the documentation files listed on this sites DOCs tab above