It looks like the next beta patch address some crash to desktop. Have you opted in the newest patch?
I have to admit that I am somewhat Steam-Illiterate. The instructions say:
To get the opt-in patch, do the following:
Right-click Galactic Civilizations III in your Steam library
Open the Betas tab
In the drop-down menu, select “opt-in”
Steam should automatically update your game
Yet I get only as far as Right Clicking on GalCivIII. No "Betas" tab shows up. I've tried it both in "Desktop" as well as "Big Picture" mode. I am still in 0.41, at least that is what the initial splash screen states. No biggie, I can wait until the next required update comes along.
Speaking of illiterate I can't get the text/background colors correct.