Ange was holding what appears to be some sort of elevation map. It appears as though something changed the geography of the island between 1986 and 1998. The part of the island where the mansion was is now shown to be the same elevation as the beach. The affected area appears to be pretty large too.
Also, Ange passed by a keep out sign left by some Toyko Metropolitan crew on her way there.
The Ange vs. Kasumi scene should have taken less than half the time it actually ended up taking. If they were planning to devote an entire episode to this scene I wish they would have at least cut content from some of the previous episodes to make room for the final content of this series.
If you judge this episode by itself it was done very well. However, there is too much to cover for the remaining episode to be adapted as well as I hoped. I won't judge this episode on how they adapt the final episode which hasn't even aired yet.