Fusion 360 post processor file for Plamac

I will consider it... the price in USD (currently $136.30) is a hurdle right now. I did indeed get a functional NGC file for cutting, using Fusion 360 with the Post Processor!

SheetCAM has a free/trial version for Linux, hopefully, been a while.
It outputs valid gcode but limits to 500 lines, i think.

They must have tightened up their policy as their site currently says,

"Note this download is limited to approximately 180 lines of generated code."

Even 180 lines is enought to cut many parts unless you want multiple parts on the one sheet.

Certainly. However the piece of wall art I cut for my first real cut project was very involved, with thousands of lines of code.

I downloaded the free trial and will see how it functions.

If you have some time, give Inkscape a try, it is very usable for plasma cutting, easy to use and free for Linux and Windows.
I use it and so do all machines i built/worked on, daily.
I have also modified gcodetools.py to output plasmac.feed.rate so the cutting speed in use is from plasmac material table.