The save status window doesn't show up until you make a change. Once you hide or unhide the layer, then the save status is activated.
Ah, yes, but if you get the warning, there is a view that has an unsaved status. You have to activate -that- view in the dialog to get the save option available.
As far as I can tell, you cannot save "all" changed layer states at once.
I was battling a drawing like this just this morning. And it wouldn't pay attention to what I told it to do. I ended up closing, erasing, and re-opening to get it to show what it should have shown to begin with.
There is only one save status per drawing no matter whether you have made the views independent or not.
BTW, I recommend not controlling the view layers independently for each view unless you have a real good reason to do so. If you need to make a layer change in the drawing, you end up having to go to each view to make the change. Not bad for a 2 view drawing...horrendous for a 10 sheet 50 view drawing.
That would be good if they all saved at once. I don't know what happened this morning. I had 7 views in a drawing. Each parts had a layer called BORDER. I turned this off in the drawing and one remained although it was in the list of hidden layers. Once I cleared memory and reopened the drawing, all was good.
Most times, I only use layers for drawings. And inevitably, it is why I need to use hidden layers by view rather than the drawing, simply because one lousy view needs a layer shown and hidden in all the others. It is an evil dance. This is also why I do not use all those layers in templates. I have very specific purposes for layers.