Try this:

- Press the Windows key and "R" at the same time.
- A "Run" window will appear. Please paste the path below in the box and click OK:
%programdata%\Stardock\Galactic Civilizations III
- Once in the folder, please make sure you have the option enabled in Windows to "Show file name extensions". If you don't, please see the following article:
http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions#show-hide-file-name-extensions=windows-7
- Find any files that end in ".dds" or ".fontdata" and delete them from the folder.

After you've done that, please perform a restart and try to launch GC3 once again.

Update your video drivers.

If you have Catalyst change the GCexe to power saving. If you have the NVida stuff then the same idea to make the program use the integrated video.

They have worked on being able to use the discrete card so maybe just updating the video driver and/or Catalyst will do the trick.

There is a post somewhere that talkes about deleating some fonts to solve some problems.

So in the folder \Steam\steamapps\common\Galactic Civilizations III\Fonts you have no gc3_font_setup file? If so here is the file, put it there and then run it and see if that solves the problem.