Like a growing number of people I have more than one screen; and for reasons of personal preference my main screen is the one on my right, while I prefer to have games playing on the central screen. SMAC always defaults to the main screen. Anyone know a fix to make it go to another screen?

I had to get a second screen myself when I started working from home. Most of these older games were not set up with multiple monitors in mind. It will always default to your primary monitor. The best way to handle this is to change your primary monitor to the one you want to play the game on. It is quick to do, only a few seconds.

Oooo...
So uh, what about a 3 Monitor Widescreen spanning setup then?
My 3 monitors are treated like 1 monitor.
And...
7680x1440... 2560x1440 times 3.
How... Much fight am I going to get from the game not understanding my monitor setup?

This game will just choose one and display on that monitor if I remember correctly. You can either go into setup and change which monitor is primary or just turn off the monitors you don't want to use for the game.