question about editing files in modded game

[Thutmosis3]

Sorry if this is a dumb question, I am totally new to file editing and what I`m trying to do is to simply modify some numbers in the descr_settlement_mechanics file so that the mod I downloaded is playable (the original mod made the financial cost of land devastation insanely high so I`m broke a few turns into having a hostile army on my land). I tried to modify this file in the data folder of the mod itself, but whatever change I made to this file no effect is seen in game, even though I started a new campaign. Did I miss something here? What did I do wrong?
The mod I tried to modify is a China-based total conversion mod made by Chinese modders.

[Callistonian]

You're editing the pip_modifier for SIF_DEVASTATION, right? Are you sure you're editing the correct file, some mods have backups with nearly the same name that aren't read by the game. Try using extreme values to confirm if your changes in the file are having any effect.