Here, download this, extract and take the .txt file, put it in your Mpqmaster\Listfiles\ folder. When you open your map, instead of checking the Warcraft III TFT.txt now check List All Files.txt box, then you'll be able to see the scripts folder.
Warmap.j is only for AI MAP, if you're using the Official AI Map from Playdota you'll be able to see the scripts folder even when you dont use the listallfiles.txt. What map are you using?