Re: pets deformed

So.....I think I solved it. 

Tried your suggestion of deleting the old cfg files and starting a new save. Used your method of camping a Sim at the pet park and waited there a couple of Sim days and all pets that spawned were normal looking. After this I exited the game, deleted caches and put the old cfgs back in, went back to the new save, and after a short period the deformed pets started appearing again. This time I used the newly generated cfg files but just copy/pasted the text from the old ones so I would not have to redo all my customized settings, but still the pet problem persisted. 

At this point I started wondering if there was something in my settings for MCCC that could be causing the issue, and after a bit of digging and looking through things I discovered that I had a setting in MC Cleaner set to clean "Heads" (under Cleaner...Item By Part) for some reason that I can't recall.... I think it may have been from a couple years ago when I was attempting to stem the flood of newly generated NPCS all having the same hairstyle. This was before I learned how to use Sims4Studio to tag items as not allowed for random and I had a couple of CC hairs that the game loved to pick for every single new Sim.. In any case, I disabled the unnecessary head cleaning and went out of the game again, reloaded the fresh save from before the deforming started, waited awhile, and after like most of a Sim week through instances of traveling, changing households, and even reloading the save I saw no more deformed pets. 

Now, the bad news is that in your old saves the broken pets remain deformed even after changing this setting back, but the good news is that if you CAS them, or just use the mod to age them to child and then back to adult, it fixes them and so far at least in my game they have not returned to being deformed, which used to happen every time they would spawn on a new lot or I would change households or even reload the game. 

Interesting thing is that I have been noticing for awhile that my pets' collars have been going missing too, but I never connected the dots until now. I couldn't even begin to explain why MCCC Cleaner is suddenly doing this just within the last few patches, but it also makes sense now why very few people seem to have had this problem since it's apparently triggered very situationally. 

Anyway, I'm not going to say with 100% certainty that the issue is fixed for good as I still need to playtest for awhile to know for sure and I don't have a whole lot of time to play sometimes. If you haven't already solved the problem yourself by now then see if you have the same thing enabled in Cleaner that I did and disable it, and then fix your pets how I described and let me know how it goes. I'm grateful that you started this thread and helped me in the right direction because I've been trying to sort this out for a month now with no success because of course MCCC was the absolute last thing I expected to be the source of the problem.