I managed my sims to use the pool at last 🙂 Thanks to @CGrant56 I got inspired by the build a room idea. However, I didn't flatten or change the terrain level. I simply created a room around the pool areas with the wall tool and then bulldozed the pools. I build the pools once again and deleted the walls. Now my sims can swim 🙂
I still can't change or add walls in the house, but I don't mind. I really liked this house and it is ok not to change it inside 🙂
I think we can call this a workaround since we are still hoping for a solution from EA. The pool and wall tools were perfectly usable before the update.
