All of us have a strange belief that the original setup is correct, despite considerable evidence to the contrary. AFAICT, there’s entirely too much cargo-cult behavior and not enough testing in the manufacturer’s production process.
For example:
The preview shows you what the paths will look like when lasered, so when you see something you don’t expect, it’s in the design, not the laser machinery.
If your machine settings claim it can accelerate at 10,000 mm/s², but it can only handle half that, LightBurn must use the configuration setting, because it has no idea of what’s actually feasible.
You’re responsible for configuring the machine and defining what’s feasible, so … LightBurn attempts to do whatever you ask.
Absent any other information, the Preview window displays exactly what your design calls for, because that’s what it does for a living.
Perhaps if you upload the offending *.lbrn2 files with screenshots of what you’re seeing in their Preview windows and photos of the corresponding results, folks around here can dig deeper into the layout.
Based only on what you’ve shown so far, however, the machine has configuration problems.