Nice. It needs a little bit more than -1 space, though: -1 and 3/8ths works beautifully.
It’s a shame that if you select only an accidental or dot in Engrave mode, and change the colour, only the notehead is changed, even though it’s not selected. (But I digress…)
You’re not accused of not searching. It really was a long time ago… And I remember there was another thread where it’s been made very clear that the tuplet tool in Dorico really allowed many stuff like that to be very accurately notated. AFAIK the playback is still wrong, unfortunately.
I’m happy to keep the dot: it’s closer to the original. I’ve never come across the notation before so I have no strong feelings either way. I was prepared to do without it if necessary. My problem was more fundamental. It never occurred to me that there could be such a thing as a single-note tuplet, so I had no idea how to enter it.
You can create a tuplet by selecting a duration (such as a quaver/eighth), press ; 3 return , then select a crotchet/quarter note or dotted crotchet to enter that note.