Since approximately 2 days Dorico has a problem with opening my very large project (although only 1 flow) but over 40 instruments. It shanks when loading the file at 60%.
I habet force a quit of Dorico and a restart orf the iMac then it worked. But I don’t know for how long.
60% is, give or take, when Dorico starts loading project data related to playback. Have you been able to open other projects without trouble? Is the playback engine running correctly? Something might have decoupled both parts, and the reboot (or just re-opening Dorico and closing it correctly) popped everything back to place.
When Dorico doesn’t have enough available RAM, for example when other programs are using too much. On Windows you can see RAM usage in Task Manager; on Mac in Activity Monitor.
I had this issue, too, and there is a thread about this already. It’s likely that the VST Engine stalled. The steps provided in that other thread show a workaround; and Ulf of Steinberg recommended to get the latest version of the VST Audio Engine, and since then I didn’t have any hang-ups anymore.