I tried locating the post where the person helped me so I could mention his/her name, but could not find it, so when the person reads this post, please stand up and take credit. Thanks for the person for his/her insight.
The solution to the "Ruin Bug".
The "Ruin Bug" basically terminates your game whenever you enter a ruin if you have made modifications in your tech tree or elsewhere.
The solution? According to the person who helped me, you need to close any loophole you might have accidentally left intact after modifying your tech tree.
For example, if you modified Facist advance to appear later in the tech tree, make sure you correct the prequired advance for Nationalism - it requires Fascism. Thanks for the guy who gave this answer!
I can now play the game with no problems and hope I don't run into new bugs.
