How to create custom libaries of pipes, valves and fittings etc.?

[a123qwertz567]

Thank you for providing this workbench to the FreeCAD community, including myself. I am using it at work to create some simple pipe systems (for example parts of a sprinkler system). In other departments we are using stainless steel pipes, valves and fittings which have different diameters then the parts provided by the workbench. This includes parts from the DIN 11851 system.

My first question is, can you provide some information how to add custom parts to the workbench. I am to unexperienced in python to understand the code here in a short time so I would be grateful for some hints.

My second question: Would it be possible to use STEP files, for example from valve vendors in a library and add them as parts? I know there is the "insert any shape" function but I am thinking of a kind of "on-click-insert" solution.

[a123qwertz567]

Well after some more time I found the tables with the measurements and found out that I just need to duplicate it and fill in my measurements into the csv.

So question 1 partly is answered answered for me. But I am still clueless of how to add/generate a custom part, for example this weldon cone, depending on the measurements in a csv:
https://www.landefeld.de/shop/media/produkte/dnmi40100esasi_153356_4524.jpg
I saw code for the generation of the pipes and elbows from the dimensions but it looks complex to me because of all the "ifs" and placement stuff :)