I'm not an expert but if you want to get more info posted so that someone else might be able to help there's something you could try that Ori taught me.
Open your civilizationIV.ini and set all items with log in their name from 0 to 1 and then start the game, load the game in question, exit the game and then post all items in my games\beyond the sword\logs as a zip file attachment here.
(Although I'm not sure if that will show the problem you're having, it just posts the technical logs from the last game you load)
You could also try opening a new thread on the troubleshooting page to get more opinions, though the moderator might move it back here.