A very strange problem

[Shia]

Hi!
This is the first time that i post in this forum and i ask someone help!
Working on my mod i've added 4 new city improvements:
*Stock Exchange
*City Hall
*Cinema
*TV station

I've tried to add also a 5th improvement:the theater.
The game works good untill it pass from industrial era to modern era.
In this moment it always crash.
Now the fun part.
I've tried to play a game with normal rules(NEW GAME) and the game still crash in the same point!!

WHY?