Overview
How to enable high and very high graphics settings.
Steps
Close down your game.
Search in windows for: %appdata%
This should bring you to the folder “Roaming” ( Users > “name” > AppData > Roaming ).
Click “The Creativ Assembly” > Empire > scripts.
Click the “preferences.script”
find gfx_video_memory 0
change to gfx_video_memory 536870912
Save preferences.script
Done.
Settings for High Graphics and Very High should now be unlocked in your game.
This also works for Napoleon: Total War.