In reply to David Gray.

@David: Thanks for your feedback. Dorico does already support 2- and 4-bar repeats: simply type %2 or %4 into the Shift+R popover to create them. Note that you do need to have two or four bars of music before the start of the bar repeat for Dorico to show it, else it wouldn't make sense (what would you be repeating?). If you find that the last system of a flow doesn't reach the right-hand side of the page, there's an option on the Note Spacing page of Layout Options, 'Only justify final system in flow...', which you can switch off to make the final system reach the margin regardless of the width of its content.