Try this:
- On old computer open LightBurn
- File->Export Prefs, save to a location that you can reference
- Locate saved file and copy to USB drive, network drive, or any other means to transfer to new computer
- On new computer open LightBurn
- File->Import Prefs, locate the file copied from the old computer.
- Close LightBurn
- Reopen LightBurn
Do you still get the New Device dialog or is the problem resolved?