Sims 2 Legacy awning / roof shadow issue

Hello... I'm having an issue with putting up multiple awnings or a roof ... I can put them up, but when I do, it plunges all my awnings into shadow... which looks really bad...

All looks fine with just one awning...

Then I add another awning...

And it goes all shadowy, until I undo the action. This was happening before with the roof and then it spontaneously stopped, and now it's started again with the awnings.

I know it doesn't seem nearly as bad as some of the issues other players seem to be having (or that I'm yet to have perhaps) but it's so frustrating and bizarre and recently affecting my ability to enjoy the game, as I've mentioned in another post I also can't put railings or delete certain little staircases... I was so happy when I found out EA were rereleasing these games of my childhood but I don't remember having bugs like this years ago...

Thank you for reading and any help you may be able to offer 🙏