From my perspective, it appears to be mostly user error, if not outright stupidity, if you'll forgive me for being blunt.
That said, there are bugs, although most of them are not gamebreaking-other than the strange issue that cropped up with tech trading that was fixed...er, I know it was fixed internally; not 100% sure if the update made it out yet-I actually don't remember the previous game breaking bug.
It does appear that it's no longer on Download.com. Hopefully someone can fix up that link. In the meantime, here are some working links:
Filefront DL & DA
Gamershell DL & DA
I can't seem to find a Twilight demo, even though I could have sworn there was one. Maybe it just doesn't exist?