Sweet! I will download this and report back. Thanks so much for taking a personal interest in helping!!
Something I've been doing a while is a Clean Folder install of any expansion/patch. It's fairly simple.
1. Move the My Documents>Electronic Arts>The Sims 3>Downloads folder to your desktop. You'll want it later.
2. Move the My Documents>Electronic Arts>The Sims 3>Mods>Packages folder to your desktop (if you have one). Again, you'll want it later.
3. In the My Documents>Electronic Arts>The Sims 3 folder, delete the following cache files (these are all regenerated every time you start the game if they aren't found):
CasPartCache.package
compositorCache.package
scriptCache.package
simCompositorCache.package
Now, install the patch (superpatch preferred).
Once that is completed, start Sims 3 and start a NEW game, NOT one of your saves. Make sure the new game loads fine. Then pick a household and play it long enough to check that everything is working - like mirrors, dressers, showers, toilets, etc. Make sure you can go into CAS with no issues. If you find errors at this point, it's an EA issue because it's only the basegame coding and time to do some internet searching. However, most of the time you'll probably have no issues. Now to reverse what you did earlier. Shut down the game without saving.
Move back the Downloads folder to the My Documents>Electronic Arts>The Sims 3 and the Package folder to My Documents>Electronic Arts>The Sims 3>Mods. Restart the game and again, start a NEW game. Go through the same checks. If everything is fine, then try your save game. If you get errors at this point, you know it's something in the Downloads or Packages folders that's causing it. If you have mods, that would be the first things I would check. Are they up to date with the current patch level? Check with the creators. If not, remove it.
Since doing the Clean Folder method, I've had no issues with new patches since Generations (and I have all expansions, just not some of the stuff packs). Basically, an ounce of prevention is worth a ton of hassle.
Note regarding MasterController for the person with all the social workers: MasterController can reset your entire town. Not just sims but every object (which can be useful if you're not sure what's borked). From the City Hall: NRaas>MasterControler>Town>Reset Everything. Give it a minute to complete as it's a lot to process. Hopefully that will fix your problem.