The ShowStation is basically a customized Windows box, and like any Windows box, it's a little touchy. The first thing you need to do is plug it in and press the power button, but before you can actually turn it on, it goes through a boot-up procedure; the red light on the power switch will flash until the boot-up is complete. This can take several minutes. Once it stops flashing, you can push the power button and the unit will turn on.
The black ethernet cable connects the ethernet port of the ShowStation to the purple ethernet port on the back of the ViewStation.
The ShowStation talks to the ViewStation via ethernet; both have IP addresses, and they look for each other when they start up. As noted above, it usually works best if the ShowStation is booted up first, but sometimes you have to power cycle one or the other to get them to resynchronize. The ShowStation IP address is 220.127.116.11 (corvus.berkeley.edu).
To check whether the ViewStation and ShowStation are actually synchronized, go to "System Info" on the ViewStation, then "Diagnostics", then "Advanced Stats". If things are working, there will be a "+" symbol next to "Data Conferencing". If not, it will be "---".
If they're synchronized, when you call someone who also has a ShowStation connected, the ShowStations will hook themselves up and allow sharing of documents.
There does not appear to be a real power switch anywhere on the ShowStation; when you turn it off the screen will go off, but the PC part of it still sounds like it's running. I have not found any way to shut it off other than unplugging it.