I tried to tie notes and I see a different behaviour from expected as you can see in the attached video.
Also untying does not work as expected, if I am not wrong.
You certainly are trying to tie notes together: two different pitched notes. Because you select both of them, Dorico is tieing them to the next note of that pitch.
Is there any chance you want to just add a slur? If so, select the first note and press S.
What key command are you using to untie?
Yes, you are right for the first part, but what about the untying, I use the “u” key, it seems that the untying is not as expected.
It seems that some intermediate tie-slur kind of thing is applied.
the rests inside the tie are causing your caret position +U shortcut not working. Ties over rests are musically not logical anyway (and the possibility of writing them is a courtesy of Dorico, I think, but they make the untie shortcut not work, if you use the shortcut on the rhythmic position just after the rests)
Please, this is a technical issue, there is no place here for accusing or defending Dorico.
Dorico makes no courtesy to customers and users.
However this seems to be a minor issue because it clearly originated from my mistake.
I just discovered this issue by chance. I also was aware of strange note overlapping when using play mode (piano roll) so I think this is related.
If it is forcing Dorico functioning, it should be not possible because if notes are created in an incoherent state it can lead to problems in a later moment, when much work has been done. Better to know instead of doing it next time at least.
Oh, I think it does:
that makes possible for example to notate and playback correctly things like this (ties between notes that are actually “physically separated”):
@Christian_R
Of course, they chose to use a midi engine so an amount of this courtesy are necessary…