It’s certainly the case that MIDI input won’t work until the project is activated for playback, that’s right. It would be interesting to know how long you’re waiting for your project to become activated, and how many instruments it contains.
They are very simple projects, the only open instuments was Haliosonic SE, now it’s Halionsonic 7.
There are only two slots loaded, (one player and one track for chord symbols).
Waiting times range from 3 to 5 minutes.
The “problem” is that I have several preset files (read-only) that I use as templates with different configurations depending on the music I have to write (for choirs, for schools, etc.).
and even saving the file with the new HS7 instrument, when I reopen the file Dorico continues to load “Haliosonic SE”, then not finding it, it loads HS7 correctly, after several minutes