I don’t know what the Record function (Ctrl+R or the circle next to the play button) in Play mode does. I can’t find anything about it in the Dorico Help file. From some of the discussions here I get the impression it’s connected to MIDI, but I’ve found no description of how (or why) to use it. Is there a tutorial source for Record?
P.S. While I’m at it, I’m also curious to know why playback in Write mode gets jumpy for projects with a lot of instruments but playback in Play mode sounds just fine. I presume the overhead of drawing notes in Write mode is involved, but it doesn’t seem to matter how many instruments are actually sounding after several minutes of puttering.