I may not have had read / experience widely enough yet
I am using FMPA 13 and working on a layout (header, body, footer) using the built-in stencil for iPad portrait. The theme is Enlighten Touch. All fit within the buondary (organe line) for this layout.
On the footer are three buttons, and have their auto sizing adjusted to left bottom for the two left most buttons, and auto size to right bottom for the extreme right button.
When launched on iPad mini (portrait), the layout occupy the entire screen (that is what I want), the three buttons drop the the bottom (good) but the footer occupy larger than its "usual" size.
However, on landscape, it seems perfect.
I must have overlooked something.