I create in Illustrator, import to Lightburn, adjust size to suit, then save the resulting as an SVG.
When I come to open that SVG in Illustrator, Safari, or any other SVG-aware app, there’s no line information, just a blank screen.
In illustrator I have all the separate components, but don’t see to be able to select them to assign a line weight or colour.
It’s driving me batty, trying to work out the correct process.
Of course I can use AI, but I tend to use SVG for maximum compatibility.
Here’s an example: https://drive.google.com/open?id=1VSKVMz7TmkdGXKoQ1jeFsr26xIrb-9Nn
Up-to-date Lightburn, MacOs 10.14.4, lots of memory and disk.