First off, nice avatar. I've actually become a fan of the new doctor myself, but before him Tom Baker was obviously the best.
As for your problem, there was a bug that could cause this if non Roman Characters were in the mod's path. However this should be fixed, at least I have implemented the work around fix and other users that reported this bug have stated that this is fixed. So you may have found a new bug. The bug must be user specific, but I'd like to fix it, as it's likely other users have experienced this and just not reported.
My intuition tells me this is some conflict with your system and the BUG mod's code. There are a couple of things we can do to try to fix this (and so I can fix this in a later update for other users). First can you turn on Python Exceptions? In your My Game/BtS folder there should be a _Civ4Config file (you can also access this in your Program File/.../Beyond the Sword folder, as there as a shortcut to it in there). In that file search for this line:
Code:
; Set to 1 for no python exception popups
HidePythonExceptions = 0
And change the 0 to a 1 so it's reads like so:
Code:
; Set to 1 for no python exception popups
HidePythonExceptions = 1
Then find these lines:
Code:
; Enable the logging system
LoggingEnabled = 0
...
; Enable message logging
MessageLog = 0
And again change the 0s to 1s
This will enable python exceptions, and will log them. There is obviously some failure occuring with the Python (as Civ4 builds it's interface in Python, and so does the BUG mod which LoR uses), and enabling this will cause the Civ4 game engine to put pop ups on the screen declaring what the exception is, and where in the code these are occuring. You can take pictures of these and post them for me, though that can get annoying. It's probably easier just to go into your My Games/BtS logging folder and upload the Python logging files (specifically PythonDbg.log, PythonErr.log, and PythonErr2.log). I'll take a look at those and see what I can uncover.
Another thing to help is to try to isolate it. As I said I believe this is an error occuring within the BUG UI, and it's python code. To be sure of this, please uninstall BUG (just for a moment), if you have the BUG mod installed. Then reinstall the BUG mod, but don't pick the "standard install", instead install it as a mod. Then try to start up the BUG mod, as a mod, and see if you get the same errors. If so we can move the debugging of this over to the BUG forums.
I would greatly appreciate the help here, and your report. Unfortunately I can't debug it on my own, as your error is computer specific, and so we need to determine what is going wrong with the software on your computer, and hopefully fix it for you, and also for other users that may have a similar problem.