Sims won't do what they are told

I only now just found out that a building downloaded from gallery can be corrupted! I did A LOT of building around 4 weeks ago. Basically built every cafe, beach, bar etc. to every world. I also did one building the same day I play with the landlord couple. Does anyone know how fast you notice a corrupted building?? Could it be the same day? What can I do? I don't want to lose 6 years of sims worlds renovations! it's finally ready. I have downloaded every building that I have renovated to my personal callery. Does that have something to do with it? Somebody also said that the corruption spreads between the worlds. So does that mean that I should play in every world, see which are corrupted and remove all the buildings in them? Can I stop this at all!? PLEASE HELP