At the moment I'm working on my first design in KiCad. I'm quite new to the world of PCB design, though hardly new to electronics -- I've lived and breathed electronics for the entirety of my existence. I am perplexed at how the rest of KiCad, while occasionally (okay, often) quirky, seems to be easy to pick up and generally "just works," but the BOM generator tool resorts to the command line and doesn't work out of the box! (But it's free, so I'm not complaining, just pointing out an inconsistency/weakness which could use some attention.)
Anyways, I was contemplating symbolic links, but that seemed too complicated. I kept getting nothing but error 11, and out of desperation signed up to this forum! And then I figured out a solution by piecing together various answers above, and so I'll share it. Giving back, you know?
xsltproc.exe -o "C:\Users\[username]\Desktop\[file_name].csv" "C:\Program Files\KiCad\bin\scripting\plugins\bom2csv.xsl" "%I"
The above worked for me. Note that I added ".exe" to the command, and neither my username nor my file output name had spaces. I am simply astonished that -- in 2017 -- Windows is incapable of handling spaces in file paths. Do any of you know if the BOM generator works out of the box on Linux/Mac, unlike the experience on Windows?