Stayed 2 nights in 2 rooms at Örenäs Slott. Overall it was nice, though there are a few caveats.
Pros: beautiful lawn area with a kids play area, mini golf, and a giant lawn to run around on, overlooking the sea. If you have kids, it is great for them to have some space to run around! The rooms were clean. The breakfast in the castle was delicious, too.
Cons: The rooms are in a separate building, not actually in the slott/castle. There is a restaurant in the castle, and one down by the water (which is walkable), but both were filled and there is nothing else right nearby except for a simple pizzeria. If you want to eat on site, book the restaurant when you book the room. Also - there was a heat wave, the air conditioning in my room (in the top floor) was broken, and I had to make 3 separate trips to reception to complain about it. Eventually they put some kind of portable AC thing in there, but it didn’t work well. I ended up getting a partial refund for the room, but I spent a VERY hot and sweaty night there.
Overall, it is a fine hotel and beautiful location, if you need to be in the area.