I have a new Ortur LM2 Pro and using a late 2016 Macbook Pro running Big Sur to run it. Any time I turn off the laser or otherwise disconnect it from the Macbook, I cannot get Lightburn to detect it again until I delete the original device and do another search and add. Any ideas of what I can do to avoid this?
Are you saying that if you try to re-connect, using the last working device profile, you can not? Try to connect using the right-click on the ‘Devices’ button. Some systems don’t automatically connect - you might have to choose the correct port. 
Yes, that is what is happening. Whenever I go to use the LM2Pro for another session, after turning it on and then starting up the Lightburn software, the device will not connect. Nothing happens if I right click (or option click for a Mac), there is nothing to tell it to connect to the LM2Pro. The blue light for the USB com port is lit so I know it is present on the USB port. Other than that I’m not sure what is going on.
So a weird update. Since I had 20 days left in my trial version, but not really finding anything else that is suitable for MacOS, I paid for an activation code and since activating, I haven’t had to refind/reinstall the laser engraver.
Did you get a different version of the software installed, or is it the same one you started with?
The same version. I only entered the license key and activated it.
I am having strange issues on mac with USB that i never had with windows using ethernet.
I am switching the MAC over to ethernet saturday. if the issues go away, I will report back.