Got it too.
The lua.log file indicates an attempt to access a nil pointer in GameplayUtilities.lua
The fix (for me) was to edit line 371 of that file and change it from
Code:
if (city:GetIntrigueLevel() >= GameDefines.CITY_INTRIGUE_WARNING_LEVEL) then
to
Code:
if ([B]city and [/B]city:GetIntrigueLevel() >= GameDefines.CITY_INTRIGUE_WARNING_LEVEL) then
thanks for the awesome fix whoward69

! i was so mad when this happened had a great game going.
anyway for mac users the path to the erroneous file is:
/Users/
YOURUSERNAME/Library/Application Support/Steam/steamapps/common/Sid Meier's Civilization Beyond Earth/Civilization Beyond Earth.app/Contents/GameData/Assets/Gameplay/Lua/GameplayUtilities.lua
note that the user library is hidden 10.7+ so open finder, select GO from the menu bar,
press down the option key while the go menu is open, and click Library
note 2: when you get to /Users/
YOURUSERNAME/Library/Application Support/Steam/steamapps/common/Sid Meier's Civilization Beyond Earth
you have to right click (or press down control and click) on "Sid Meier's Civilization Beyond Earth" and select Show Package Contents, then you can navigate to Contents/GameData/Assets/Gameplay/Lua/GameplayUtilities.lua
it's still line 371, i recommend editing the file with textwrangler (free)
final note, if you're on a mac with auto graphics switching download gfxcardstatus and set it to always use the discrete graphics before launching the game.