I noticed your question shortly after you post it, and decided to unswer, but I was at PC where I couldn’t check how I am doing it, and yesterday I had absolute 0 time.
When I have read KiCad doccumentation (just before 4.0.7 was relesed) the only PCB design stage I felt I understand nothing about was generating the BOM. Now I know a little. In 4.0.7 BOM generation was only from Sch and I didn’t check yet how it works at PCB.
Step by step:
Haveing one of demo schematics open Tools|Generate Bill… and in opened window I first click Add Plugin button. Then I select directory: C:\Programy\KiCad\bin\scripting\plugins.
By the way - I always install KiCad not as it wonts to be installed (in Program Files) but in created by me folder “Programy” It is because Windows has something against modyfying C:\Program Files\KiCad\share\kicad\template\kicad.pro but nothing against if KiCad is installed not in Program Files. I trhink that when you open new project kicad.pro is copied for you. So after installing my first step is to edit that kicad.pro file. In 4.0.7 list of schematic libraries was in it. In V5 kicad.pro is less important, but I think (not sure as I have not really started to use V5, I am only collecting my footprint library now) that for example if you define your frame for schematic in it then it will be used for your “New” project.
Comeing back - from that directory I select bom_csv_grouped_by_value_with_fp.py. and KiCad fills the Command line as needed.
Now button “Generate” runs this plugin. As a result in project directory you get two files (project_name.xml and project_name (without extension). It is easy to overlook that second one but it is csv promised by plugin.
I don’t know what for is that xml. After adding .csv I can open it with OpenOffice.
I have checked that If you change “%O” to “%O.csv” in Command line in Bill of Material dialog box you will get your csv with right name but I don’t know if it is the right you should do it. May be it should be done by modyfying something in plugin file, but I don’t know python.
People here helped my to change csv I get from this plugin. If you are interested read: