I followed what you wrote and the error doesn't show up anymore. But now I have a new error which states "Invalid FST," I'm assuming it has something to do with the game itself as the game.key worked. But I don't know what exactly may be wrong with the game.
I'm trying to install Call Of Duty Black Ops 2 as a Wup. The game was only released on disk so I can't use USB Helper.
I'm using wud2app, and I keep getting the error that the size of the common key is wrong. I have wrote the common key on a text document and then renamed it to "common.key"...