I have mixed feelings about this update. The stair improvements look amazing. But the many warnings about backing up saves and mod issues sound awful. If even EA is saying mods will break, this situation and code changes must be severe. Hopefully their info for modders will help.
The trailer is also odd. Adding pack exclusive interactions to info about a base game update feels like it shouldn't be bundled. Also the board with the family tree : why does the narrator call it a tapestry when it's clearly not a tapestry? Feels like the name makes as much sense as the arrow slits in the castle kit.