No, I'm not, I have absolutely no coding skill at all! But I have used mods for various games and for various reasons. The first time, it fucked up my game - but that was because I tried to be greedy and "choose both" for one of the most important decisions in the game, and the game just didn't know how to react to that. For full honesty, I suppose even then it didn't fuck up my game in terms of "breaking" it, it just carried on as if I'd picked secret option "C" instead of the "A and B" that I'd actually chosen using the mod.
My experience is a good lesson in "using mods responsibly", and every other time I've used a mod since, in any game, I've had no problems whatsoever. I have however, had Ren'Py errors on games I've played without mods, just to say that "mods broke your game" isn't always the answer.