Dorico mixer showing only one instrument

Dorico community,

New to Dorico, and I’ve tried porting a Sibelius project in using XML. It looks suprisingly clean. But when I go to the mixer, I only see one instrument listed. (It’s a string quartet.) Can anyone advise?

I’ve tried to attach what I’m seeing.

Thanks,

Mike

NotePerformer uses its own mixer, in its VST window. (Click the e button.) Then everything goes out from there, into one stereo channel in Dorico.

Thanks, Benwiggy. I see that now. Appreciated.