Omg. Thanks for that. There is no way I would have figured that out on my own.
Also, I didn't have the issue of having to re-download the main game. After clicking the two DLCs, it did a download of a few MBs. That said, your situation makes me laugh a little, when TW2 originally came out, and stored everything in one data file, causing you to re-download almost the entire game every time they released even the smallest patch/update.