Hello,
As in topic, I am using AC 20 and I have this issue with viewing my project. When working on project map I'm hiding (for example) all layers except walls. Then, I press F5 to check something in 3D. This is the point where it bothers me soooo much because after changing back to 2D via pressing F2, AC 20 shows again all layers.
Sometimes i need to hide some layers and change views from 3D to 2D many times and It's painful to hide the same layer again and again. It somehow resets "current working" layers.
Once again I am working on project map when doing this kind of work, not on view map.
In previous AC this was never a problem. When I hid layers they remained hidden no matter if 3D or 2D.