The Neobook GUI wrapper has been there for more than 6 months, and this is the first time anybody reports it as a "malicious site". Reading the Google report I would hazard a guess that Google has found something malicious somewhere in the website itself. Not in the GUI wrapper. Perhaps the website was hacked and it has now been fixed, or perhaps the website showed a bad advertisement banner or something like that. The Google report says it found only 1 instance.
Tip: See the Virus Total
and Jotti's Malware Scan
websites to scan a download with lot's of virus scanners.