I’ve looked at all the threads on this and have done my homework without success. The final stave of a piece I’m working on only fills about 75% of the margin (and other stave lengths). I tried both adjusting the note spacing under setup to different percentages and switching it off with no response what so ever. Also tried, in this instance, adding another bar to the last system from the system above but Dorico refuses to do this. The system is a bit cramped as is and would look better going to the margin.
Is this a bug?
Layout options>Note Spacing … uncheck “only justify final system…” … ? 
Thanks for the suggestion fratven, tried that, didn’t work. However I did find that adjusting note spacing as much as I could to keep everything neat and tidy and then unchecking ‘only justify final system’ did the trick.
I’m extremely surprised that didn’t work, Richard, because that is the only feature that would produce a final system that doesn’t reach the right-hand margin on the final system.
I tried all the available options with no results, but as I did find a workaround all is well
Well, Frank’s advice to you was absolutely right, and you should definitely remember that option as the means to make the final system of a layout reach the right-hand margin in all of your future projects, because it is at present the only option that makes any difference to this.
Daniel: what I did was go to setup>note spacing> only justify final system… and uncheck that with no result. Then I tried it with different percentages with no results. I also tried transferring several bars from the frame above by selecting the first and last note of the bars I wanted to make into a system on the last page and nothing happened.
What I did do worked, and fwiw I have another piece that had the same problem where unticking the check box worked fine.
Maybe the frame was locked in the first instance? I haven’t done much looking into that yet.
It is possible that if you start trying to do too much you may confuse the program into working against itself. Probably backing up a clean file before experimenting (which I do as well–it’s a way to learn) gives one a clean slate to go back to. I suspect if you had simply unchecked the last system checkbox to begin with, it would have worked but that what you did ahead of that resulted in some mixed signals.
Hey, most of us stumble into this problem. Each new iteration of the manual and revealing post here teaches us more.
I never thought about this until this point, but I didn’t realize I have to manually back up as Dorico doesn’t have that capability yet.
Even though I use another notation program that offers automatic backup, I have never used it; but notation files are not so large (although Dorico files are larger than some other programs’), so I back up before I start work on any important (or possibly important) file and before I try something risky or new. I use a yymmdd datestamp at the end of the file (name170110.dorico, for example) so that files can be arranged sorted by name most-to-least recent. I add a letter at the end if I do multiple backups in a single day.
For experimenting, it’s always worth creating a duplicate copy of a document to work on.
However, I would generally expect backups to be a feature of the OS, rather than each app I have.