If so drop all the files that came with the mod in your game's directory, depends on where you've brought it it should be. EDIT: maybe you haven't took out the mods files from the folder where it comes to your game's directory. Funny fact: was making a mod today, and when I tried to install it said that. And it was because I had the files in another folder inside the games's directory :P
Not trying to bug you but what exactly is the game directory
It is where you told the installer to place the installation of your game.
That's it, but it changes if you have the Steam or the Beamdog version, but knowing where its located is beyond my knowledge, I don't have the game installed now and I tend to play in iPad.
Comments
And @LiamEsler can gives better answers.
EDIT: maybe you haven't took out the mods files from the folder where it comes to your game's directory.
Funny fact: was making a mod today, and when I tried to install it said that. And it was because I had the files in another folder inside the games's directory :P