From "Live Traffic" individual block or Block this network do not work. Upon going to the next screen where you block the network via the red underlined link, it shows in the Advanced Blocking page, but on the right it seen that nothing is being blocked: 0 blocked hits, Last blocked: Never ago. Yet I continue to see IPs from this network. The same is true for blocking individual IPs.
Also, on Blocked IPs page, "IPs that are blocked from accessing the site", "IPs that are Locked Out from Login", and "IPs who were recently throttled for accessing the site too frequently", there are no entries.