While at home or on free internet Xamarin Studio works fine.
However at work it is unable to contact Xamarin at all because we have a secure proxy for all internet access, my browser settings work fine and have to assume Xamarin Studio uses them for connectivity but (like quite a few things) it's unable to work where authentication is involved.
Could we have network settings options available in the tools menu so setup a proxy connection, seen this done in several other apps and seems to work quite well (mostly in my source control plug-ins like GIT)