If you have a situation where a vector doesn't close, especially with circles, you can help mitigate that by turning on the 'Hide Backlash' feature in the Optimization Settings in Lightburn. This is what the developer says:

You can find the official LightBurn Documentation here:


NOTE: This setting is a 'hack' to help with mechanical backlash by altering the motion planning in a way that is not efficient most times. and it disables a few of the other optimization settings when its enabled. so i would leave it off unless you need it:

Here is how to turn on 'hide backlash' in the optimization settings in lightburn