Did you happen to notice exactly when the intrusion notice popped up? Such as, had you just moused over an ad?
I just looked at the SimV download page a few minutes ago and didn't get any alerts.
This reminds me of an incident several years back, when I moused over (did Not click on) an ad on SimV and got an alert that my Norton security program had blocked a "drive-by" download of a particularly nasty bit of malware that was going around at the time, that included a key logger and a Trojan. When I moused over the ad again I got the same alert, and since I was looking for it that time, I saw exactly which ad triggered it.
I contacted SimV and sent them the information. They ignored it, and for a whole month that ad ran, and every mouse-over triggered that attempted drive-by download.
I posted a warning about it in this forum and immediately a SimV fan rushed to post in SimV's defense, claiming that it wasn't fair to criticize SimV for letting the ad rum because if they removed it they'd have to give the advertiser their money back and that SimV needed the money.
They went on to say how FS download sites couldn't operate without all the advertising they could sell, a curious position to take for someone who was a member of this site, which operates rather well without selling any ads at all.
Bah!