See here: http://imgur.com/Aud7yL8
Mostly text isn't displayed anymore / only sporadically. Affects menus, too - but everthing (including saving) is still working, even if in Helen keller mode.
Everything's fine (for the time being) after reloading
[edit] I've made the following additional observation with dual monitors, triggering the issue:
Running I started GalCiv III on one monitor, "New Game", "customize Galaxy" step, selecting "Opponents". I switched to the second monitor; GalCiv III remains visible with animations running on the first (which rocks!). After 5..10 minutes of the game running in background, text just vanished.