Make sure it's either inside a mod folder's addon folder, or if you have to, inside your main addon folder (not recommended). Also make sure you've got the necessary files RUG_DSAI.pbo and RUG_DSAIGen.pbo au minimum loaded, or the other languages will try to access scripts they can't get to.
If that doesn't help, it might be interferring with some other addons: try it with vanilla ArmA with no other addons loaded, and go from there.
Your download might have been corrupted: try re-downloading the file (it should be about 35mb .rared).
And finally, if that's no good either, post a screenshot of the error and we'll see.