It ran the login screen, but that was it. I couldn't get it to login no matter how much I tried.
So I figured I'd uninstall and reinstall it. When the uninstaller ran, it started going through all my other game's folders and wiped out all the other games installed on the same folder of that drive (meaning, all of my major games like mass effect, dragon age, sims 3). I have no idea why this happened. I've lost all of them now and all my progress.
I redownloaded the pack from the website just a few minutes ago, and managed to run it successfully this time, but again, I have no idea what happened there. It should only have uninstalled what it installed.