This does appear to be a latency issue - I’ve opened the MIDI file in Cubase and all the notes look to be about 30ms early. I tried shifting them back by 30ms and saving the file, then loaded that into Dorico and all the notes now appear. So whatever latency setting you currently have in Dorico, try reducing it by about 30ms. I’ve attached the adjusted MIDI file.
There is a bug here, which I’ll log, but experimenting with getting the correct latency should let you get better results.
Regarding support, generally you will get very good support on the forum - there’s a very good community here. Also, I wrote the MIDI import feature, so this report has got to me a lot faster than if you had gone through your distributor.
MIDI Capture.zip (1.36 KB)