Networking connection lag

Hey, I just tried the networking example - http://unity3d.com/support/resources/example-projects/networking-example.

Uploaded to our website and had the guys at work all connecting into a master server.

But a few issues…
a. 2-3 times wasn’t able to connect into the server
b. slow for server to appear (not always)
c. doesn’t work on mac

can anyone shed light on this?

Is there any more information you can give? Code, circumstances, etc?

I am just using the standard networking example from Unity3D. I am going to try the M2H tutorial and see how that goes…