Having the same problem.
It's super annoying and I'm pissed at ea, makes you feel like the game is not worth its money since they are taking so long to fix it.
So another Game Pack announced and there are still issues with this bug and other problems. EA need to put things right first because another Game Pack will just add more problems. My Wallet will be put away until EA get a grip on these bugs and problems.
Just got a new powerful Computer and lighting lag is still there on large and open lots with big rooms. Depends also which town you are playing. Newcrest is the worst and Del Sol Valley is the best. EA need to look at their Game and Lighting Engines. Using an Eight Core Intel CPU and Asus RTX 1080 Super GPU. Fastest Ram and and an M2 SSD Drive. I give up.
Kind regards James.
FINALLY A FIX!!!!! It must have been a total mess in there because it took forever.
I'd like to thank all the people who posted in here and kept the dream alive... and especially those like myself who bashed EA with significant but reasonable force at almost chance.
I haven't played at all since June because of it, no idea how to sim now, it'll take a while to get back into gear but it will be done.
Anyways, nicely done EA, you rich maniacs.
Just to add another person to the list.. I like to build homes where sunlight and moonlight is cast down into the deeper levels of the structure using cutout shapes (trying to avoid a crazy electric bill is one reason) Imagine my surprise when an update a few months back broke that.. you guessed it visual dirt floors......... but HEY light still casts through it! Sure is an eyesore to see the dirt though.. Moving the camera you will see this sorta shimmer effect over the affected areas- no doubt the manifest glitch/bug. Anyway i'm patient, I hope it does get an eventual fix.