To use & mod the files :
- Launch the game, click on the "Show Data Folder" icon in Settings -> Profiles
- Locate the "Mods" subfolder and create in it a folder and name it to whatever you want
The Mods.ini is in the same folder, beside the "Mods" subfolder.
For example, for the player base, you'll get : "Mods\MySyperMod\Ini\Players.ATP.ini". (don't add ".ini" if you don't see it at 1st)