(It's been a LONG time. But now I am back with Sims 4)...
So, Sims 4 updated last night. I'm late to the game and just got Sims 4 like a week ago. Bought it, Strangerville, Vampires, and one other stuff pack that matches those weirdo games. (Nothing custom or downloaded other than official stuff so far, on a Mac)

I was following SimsVIP instructions for building a split level basement and up until last night, it worked. After updating, went to play my lot and the split basement is showing dirt for the floor that is to be deleted to make the "loft" portion. You can't delete this either and what's worse is that when you add stairs, they glitch through this "dirt" level and the floor does not open up where it usually does for the stairs.

See this picture:https://farm8.staticflickr.com/7587..._5f1320cf1e.jpg well, where the plumbob (the white dot) is, should be where there is no floor to make the loft part. But in my game, where that white dot is, is actually now just dirt I can't delete.

Making splits levels regularly works fine as you would normally and this dirt does not appear.

So, if this is a bug or glitch, tell me how to fix it. If it's something else, tell me what I am doing wrong.

Thank you!
Antonia
(maker of Pooh Corner for previous Sims)

(Just searched EA forums for an answer, seems everyone is having this problem now after this patch. No fix yet.)