As seen in the image, all slurs are rendered nicely, except just two.
Of course, I can manually correct their curvatures, but can’t help asking: what could be the reason for just one particular interval to cause such a behavior?
Igor Borodin
Could the accidental be the reason?
Indeed! Removing accidental does restore normal shape.
Unfortunately, that can’t be used as a work around - employing a key signature would invariably require some other notes to have accidentals.
Perhaps, there is a specific setting in Engrave that could help, but as far as I can see, the only setting for slurs related to accidentals is a possibility to bisect the stem of flat.
Just to illustrate the point:
Regardless, thank you for your hint.
Update:
Setting manually optimal number of bars per system does help; therefore, I consider the issue being closed.
IB
Dorico doesn’t automatically do everything perfectly, but IMHO it gets things right an awful lot more than Sibelius or Finale. In the fringe cases where it gets slurs wrong, you have the tools to manually tweak. I do hope that in the future the development team will have the chance to look specifically at slur behaviour over system breaks, as well as with accidentals.
Agree. That’s why I added an update assigning the issue a status ‘closed’.
Ah. I took “being addressed” to mean “in progress”, which is not quite the same thing as “closed”.
Thanks. I re-worded the update note 
We do have a number of ideas about how we can further improve the default shape and placement of slurs in these kinds of examples. There will always be pathological case that cause problems for an algorithmic approach, and at the moment the kinds of cases that expose weaknesses in Dorico’s current approach concern short slurs between notes that are a long way apart in terms of pitch, and adding accidentals, which effectively force the slur to be more or less vertical, make things worse. A bit of adjustment in Engrave mode should, until such time as we’re able to devote more time to this area, resolve the issue relatively quickly, and hopefully you are still in the aggregate saving a good amount of time by using Dorico.
Absolutely!
Everybody understands that perfection is not a fixed state, but rather a direction for moving forward.
