I ran Boxes for the first time and was presented with a nice, full-screen window.  It has some explanatory text in the middle of the screen, and a list of steps on the leftmost sidebar.

... And it took me a while, on my big monitor, to *see* the little buttons on the top-right of the window where the "Continue" button is.  I didn't expect the controls to be there; they are far away from the explanatory text in the middle, which is the first thing one sees.

Screenshot attached.