Editing spells, skills, units, etc.

Hello, I recently learned how easy it is to change the things mentioned in the topic. This blew my mind, and I started customizing the game to my liking, but I don't understand a lot of things:
For example, when exporting sptraits.txt and opening it in Notepad, the column positions get messed up, turning it into a jumble. What do the 4 columns of Spell Ai Value mean? Where can I find the parameters for numerical bonuses from skills? How can I fix these things in HotA (I hope this is a correct question, and the authors don't mind)? And many other things.

I'm sure all of this has been described somewhere, but it's extremely difficult to find. Is there a manual somewhere that describes all these game archives and their contents?