Hi, I have a string quartet totally finished and I want to start a new one (importing an existing midi file) with exactly the same instruments (and the same vstis for these instruments with all the settings).
I tried a new flow (and also a “save as” with deletion of notes of the previous quartet). Then, midi import. In any cases, Dorico creates new instruments not reusing the previous ones.
How can I do ? Sure I have missed something with the midi import feature (I tried the “reuse existing instruments” checkbox, but it doesn’t change anything)
You can indeed import the tracks into your MIDI file into the existing instruments. Make sure that each track is configured such that it corresponds to the instrument held by the existing players in your score, then click the “advanced options” button to show the list of players on the right-hand side. Select each of the tracks in turn and make sure that it is directed to the existing player, rather than to a newly-added one.
Thanks a lot Daniel. I didn’t try the “advanced options” 
I thought it was automatic 