Thank you for your reply. I know about zoom mode (2 icon sizes). See picture, where the zoom mode is shown, but distant icons are smaller (36 px) than the 70 pixels they are set to. I have not seen the icon movement again. The "show indicator under running programs" does not seem to work, or at least is not discernible.

There are "advanced tweak" options which are inscrutable to me. What does "allow tabbed docks to automatically dock to the edge of screen when dragging" do? Or, "show flyout menus as normal menus when they contain over 80 entries"?