Not able to finish a single circle

For the purpose of this topic, self-assembled is similar to self-built - I was basically asking if you purchased a machine that was ‘ready to run’, or had assembled it yourself.

If the belts are too tight they can restrict the movement of the stepper motors. They should be snug, not slack, but not ‘guitar string tight’ either.

The engraving speed is just the speed setting in your layer. Your image didn’t show the cuts window, but you can configure LightBurn to show mm/min or mm/sec, depending on your preference. The travel speed is normally set by the $110 and $111 parameters in the controller itself. I just covered that for another user in this topic: Slower blank movements, is it possible?

Pixel size is ‘Interval’ in LightBurn. The default is 0.1mm. The working size is the page size, and the ‘weak power’ value can be configured in LightBurn by enabling the ‘Laser Fire’ button in the device settings, and then adjusting the power value in the Move window.