Hi!
When in Layout Pane, the list of Presets is not ordered in any particular way as I see, at least when it comes to the buttons.
I think it should be ordered either by preset type (Buttons, Text, Images…), or Preset name. Any would do. 
Right now, for example I have one button preset at the top, one in the middle, and one at the bottom. while other elements do seem to be grouped together. (my buttons all start with Btn).
Thanks!