Dear Cubase Community!
I’m an absolute beginner and probably my question is very simple, so I really hope that someone could help me with this. For a scientific project we generated short chord sequences as wave-files, which I then exported as MIDI-files in MuseScore. Afterwards I imported them to Cubase. Now I confront the problem of not being able to play them. The wave-files are recorded as piano, tromboe and clarinet and I am wondering if I newly have to assign instruments to the MIDI-tracks in the first place in order to make them audible…?! In order to check for that, with the help of a tutorial I put in any number for an instrument in the field of “program change” in the “list editor”, however, again you could hear nothing. I would be very greatful to get some helpful advices, thanks a lot! 
Greetings,
Welcome to the forums.
If you import MIDI files, you have to assign instruments to them in order for them to play.
To keep things simple, I suggest using three Instrument Tracks using HalionSonic and then select a Patch to play each part – Piano, Trombone and Clarinet.
This is not the only way to do this, but it might be the easiest for you.