The thing is that every time I pack a mod I get this pop-up :

And even though the changes are there when I unpack it, there is no effect ingame.
I thought it might be because I'm on steam (it apparently has problems with mods) even though I use other mods fine, but it is the same in origin.
Can anyone tell me what exactly is wrong?
EDIT : I just realised this is in the wrong forum and belongs in Mod Help. Sorry.