If you don’t see the Lumos option in the device list (top right of the software) when connecting for the first time, this may be due to cache or network delay. Just select any “WeCreat On USB” option — the model shown below doesn’t matter — and the USB connection will work. We are fixing this in the next update.
If the USB connection fails, the laser head may not be properly installed. Loosen the bottom knob, remove the laser head, and connect it directly to the computer with the included white cable to test. If it works, power it off, reinstall it securely on the frame, tighten the knob, and try the USB connection again.