When I open the Interactive Atlas on either of my laptops, the buttons just above the 'star chart' don't appear. I have to run my mouse cursor along the top for them to appear. One laptop has and AMD graphics card, the other an nVidia, so I don't think this is a vendor issue. Not complaining, just letting you know.
it happens when you have screen scaling bigger than 100% (On Windows 10 is under Display Settings in Control Panel). In my laptop I have it by default on 125%. Since version 4.0a the map appears on the Interactive Atlas but the buttons are still hidden.