As part of a school project on Procedural Content Generation, myself and Ulrik Brønsted have concocted a wonderful third party app to improve the way one can play Civilization IV.
Currently this mod is available only for Civilization IV Beyond the Sword. This mod is at version 0.5
What it does is it creates a map for the game based on a satellite image. It creates the terrain height, types and level of woodland. Currently, rivers are not created and resources are not placed depending on their position in the real world, which is something the developers want to do for future build. Besides these, some lower lying regions might be represented as under water, such as the Netherlands or the Po River Valley.
Download and unzip to any folder you want. This is a third party app and does not require the game files to function. Once extracted, double click on the .bat file to open the app.
Drag a rectangle on the image of the world, write down the name of your map and click on Generate Map. You can fine tune the selection by modifying the values on the right hand side of the interface and then click on re-draw rectangle.
Once generation is completed, you will receive a pop-up message and the map will be in the same folder where you extracted the mod. Then you must copy the file created to the PublicMaps Folder found in the Civilization IV Beyond the Sword folder. Once done, you can start playing the map as a Scenario.