Pass on this one. For me the capacity count shows the right amount of used space and total space even for the operating system.
Western Digital decreed that no owner of the My Book Live is allowed to access the Dashboard UK from outside their own network and didn’t bother making this an option for the owner.
Install this: http://support.apple.com/kb/DL999
Once done when you address the My Book Live remember to put .local at the end of the NAS’s name. So if your My Book Live is named MyBookLive then use the domain MyBookLive.local