"For Rent" expansion added numerous issues

I have most of the expansions and a handful of packs for the Sims 4. The newest one I got was the "For Rent" expansion.

Deactivating mods did not change anything. Even when I deleted the cache afterwards. It makes no difference whether I have my custom content active or not. I have no mods that include scripts.

I started the Toddler challenge with one adult and 4 toddlers and moved them into an apartment. Numerous things do not work properly.

Regularly interface elements will not be responsive: I hear the clicking sound, for example for tutorial popups, but it won't open anything. 
Or elements are missing from the interface entirely. For example when there is a holiday, I will see the holiday banner but the icons for the activities will be missing.

The worst thing is that my Sims behave abnormally. When I add an action to give food to a toddler, my adult sim will either stare at the toddler for multiple ingame hours. Or they pick them up, put them down, pick them up again, multiple times. Nothing is in the way, no other adult sim interfering. It sometimes works, sometimes it does not.

That's happening with all care interactions. Giving a bath, reading a book, etc.

Sometimes my Sim will not go to work, with no explanation given. There is a nanny, the sims needs are topped up, nothing is in the way. They won't go to work even if I click the "Go to Work" button. They will just continue doing random other stuff.

At other times my sim will be at work supposedly, their icon is faded and they have the suitcase symbol. But they are actually at home and I can give them activities to do, which they will do.

Most of the time my Sim is in underwear. Even though they have an outfit for every occassion. Or everyone, including the toddlers, will randomly switch to winter clothing indoors when I resume the game. It doesn't matter if I have custom content activated or not. This does happen with just original Sims outfits.

The neighbours will be loud, but no one is there. I broke into the neighbours apartment and no one was there.  When I tried to go back home it was impossible because apparently there was a "social event" happening in my home. I had to force quit the game to make it work again.

Sometimes goo, the nanny, or random other things / Sims are apparently entering / spawning in the apartment but they aren't really IN the apartment. They will tell me they need to go home, but there is no one there. Or my toddlers have actions to interact with them, but they can't reach them (because they aren't really there).

In general my sim will randomly not do actions. Without a reason.
Othertimes action will stay in the action stack, even though my Sim already did them (e.g. hiring a repair service). The repair sim will come, fix, get paid, but the action of hiring someone will stay in my action stack and even when I cross it out, it won't get removed.

What I already tried:

- deactivating all of my mods (I only have custom content mods, no scripts)
- restarting the game multiple times
- playing another household in an apartment (the same issues)
- playing a household not in an apartment (it's slightly better but the interface bugs remain)
- deleting localsimtexturecache.package and localthumbcache.package