Nostalrius Begins - Quality wow vanilla realm (1.12)

So I used the client posted in forums to download Nostalrius, and right after that my browser was infected with DNS Unlocker, an incredibly irritating adware virus. Is this purely coincidental? I do not recall downloading anything else from anywhere else, except for battle.net off the Blizzard website. Was a pain to remove it, and now that I did, I'm somewhat reluctant to redownload Nost in fear of it happening again. Can someone make me feel better and confirm that the client download is safe and that I messed up somewhere along the way?
Thanks.