Thanks for uploading the 2 sample files, I noticed the lines in my version where missing, after some investigation I found I was using Line instead of line. Fusion read everything OK but it didn’t work in chrome.
I’ve updated the plugin also borrowed a line from your example so it scales to fit the browser window.
Here’s the output now, one tip run simplify on the curves first.
Karte - ExportSVG test2.svg.txt (109.4 KB)
And the Plugin
ExportSVG.rhp (23.5 KB)