Any answers yet xD? I'd actually like to know where to start as well, I'm currently just fiddling with the current created mods, but I would really like to know how to create new mods.
I've seen somewhere that you can make them using c# and javascript, but I can't find it where again
I ended up doing the same as you, I went over the documents and just checked out how some mods were structured and kinda went off of that. The documents provided are vague and a little hard for someone who never used unity before to understand lol, ended up googling everything.