When you switch from Setup to Write to Engrave you always see the same layout displayed.
However, when you switch to Print we seem to be displaying whatever layout was previously displayed on Print. This caused me a bit of grief recently - I had two layouts that were very similar and when I switched to Print it was not obvious that I was printing a different layout.
This is doubly confusing since Dorico displays the name of the layout you were just Engraving on the top. Is there a purpose to this? Why not simply control the display (and printed) layout from dropdown on the top like on all other screens?
This can indeed be confusing. Part of the reason is so that you can select more than one layout (on the left) and select to export or print at the same time. I agree that it would be helpful if whatever you were most recently viewing in another mode was the same thing displayed when you switch to print mode. (It would also be super helpful if there was a “preview” mode in engrave mode where it would fit the score to screen and strip the whole interface away so you don’t have to switch to print mode to preview the score easily.)
I’ll guess that part of the reason for the current behavior is because of the workflow that Dorico proposes: you do all your writing, then fine engraving, and then in theory, you only switch to print mode at the very end. In which case, switching to print and seeing the first (default, full score) layout makes sense.