Ahh, okay, try running in a window (press apple m) to get OpenGl rendering to work properly too.

It works fine on a LAN between macs and PCs, no network problems at all. And if you use the OS X installer and latest patch the game works seamlessly, albeit only in software rendering mode (hardware rendering has some serious problems on my machine!). It would be nice if hardware rendering worked, but all you really miss is the perceptive effect and a few graphics tweaks.