Have you tried any of the other big mods? Do you have any trouble running those?
I suggest you take a look here: http://forums.civfanatics.com/showthread.php?t=281603
Code:
If none of the above works, please enable python exceptions. (Open up the _Civ4Config file found in the Beyond the Sword folder. Search for:
; Set to 1 for no python exception popups
HidePythonExceptions = 1
Set to 0. Reload the game and post in the thread the error message that comes up for additional assistance.
This helped me. Thank you for your advice.