The Sims 2: Legacy Collection - New Beach Lots Have Incorrect Terrain Paint

Same issue here.

Newly create Beach Lot generated the sand terrain texture wrong and it just strips of multiple lines.

I have that issue as well. I even got the updated version on Steam. Oddly, it's in multiple of lines which unsure if it from the patch or me running it on Linux with Proton. I did even tested Ultimate Collection version on Linux via Lutris and hadn't have that bug.

Same Issue. Even if I paint it over with new terrain, it will morph back. And the shoreline will alway stay on that spot and can't be painted over.