Happened to me too after a lot of turns. Igot the window "Out of memory" and a window "C++" which stayed empty...until everything CTD. (See image)
A few turns before it happened, images of Black Widows and Trolls were no longer visible in their medaillon when I got the battle window (spiders attacked my caravans almost every turn).
And so the end of the debug file is thousands of the same line telling me:
Debug Message: WARNING: (CD3D9Renderer) ::CreateTextureFromFile failed to auto generate mip levels for texture: C:\Program Files (x86)\Stardock Games\Elemental\Gfx\Medallions\BlackWidow_Medallion.png. Attempting to use 1 mip level.
Debug Message: ERROR: (CD3D9Renderer) ::CreateTextureFromFile failed to create a texture.
Debug Message: Texture file name: C:\Program Files (x86)\Stardock Games\Elemental\Gfx\Medallions\BlackWidow_Medallion.png Mip levels: -1 Usage:0
With Black Widow sometimes replaced by "GiantClothed" or "Fertile_Plains"
The debug file seems to big to be sent to pastebin.com...so I had to cut it. But the end was just thousands of lines of the 3 variations of the 3 lines above.