Tech, gilleda won't be able to send samples as they are all Web Shield detections so I don't know how we can proceed (without pausing web shield to allow download, a risk if a correct detection). Even sending the links to avast may not help, I don't know if they could check out a problem on a site using the Chinese Simplified character set?
I checked out the www . differsoft.com link with DrWeb and nothing came up, so it could possibly be an FP but there isn't much we can do to further investigate it. SiteAdvisor remains Grey so it doesn't appear to be able to check it out either.
However, when connecting to it with firefox and web shield enabled the same avast alert. Getting past the initial page I can enter other pages without alert.