I don't understand what causes this nor do I understand what I should do. I make regular backups, so I usually just toss the current Sims 2 folder and replace it with my backup and play again. However if I could do something to fix it I would rather try and fix it if I could.

Recently what I did was load La Fiesta and move 6 half Alien Sims from the bin to one of the Dorms that had 2 Sims and then I made sure that each of the new Sims had claimed a room and set their Major to what they desired.
Then I saved and quit.

Unfortunately when I tried to Load the La Fiesta Neighborhood the game immediately crashed.

Suggestions?

Also anyone know why it would crash?