I think part of the problem comes from a change made in Access Controls when updating, where 'Cancel' used to actually mean 'back' because it took you to the previous panel. It was changed to 'Close' (a step in the right direction) and I suspect that change propagated to the System Settings panel.
I think a little more granularity in the code would help. I think users would have a better sense of where they are and more comfort in navigation if there really was a 'Back' button in the places where the command returns you to the previous panel.
Even better, IMO, would be to make all the 'Update' context menus open a popup dialog rather than replacing the whole panel, which makes the user think they've gone to a whole new place. That makes 'Close' ambiguous.
It's also somewhat confusing that for some dialogs, you have to save again after closing the dialog and for some you don't. Changing the 'Save' button to 'Done' helps with that, but there should really be an "unsaved changes" warning like in the old days.
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