That Strange Red, White and Question Mark Thing, Please Help

I am having this SAME issue. I downloaded eco living (I have NO MODS) and I got to play it for a couple days, then all of a sudden some of the floor squares were question marks, which isn't even the worst problem. The main problem is that my sims were no where to be found and all of the doors were deleted. I deleted all of my saved games and was going to start fresh, but now CAS doesn't work AT ALL! What the heck is going on here. I have a Mac. I believe it was after the latest patch that everything went awry!