Plutonium

Ive installed call of duty WAW on steam and have setup the plutonium launcher and have selected the correct directory path for the game. Windows: > program files > Steam > steam apps > Common > Call Of Duty WAW. when I click play the game does not open and says that I have selected invalid game folders. I have closed the launcher, run as admin and uninstalled the launcher however each time I try to run the game it comes up with the same message. Please help as I am stuck.