Thought I'd follow up after finally getting it working. Here's the final version:
[Media Type]=[Audio] [Genre]=[Classical] [ClassGrouping]=[Chamber],[Concerto],[Electronic],[Orchestral],[Solo Instrument],[Vocal] ~nodup=[Composer/-AMG Work Name] ~sort=Random ~expand="Composer - Album - AMG Work Name" ~limit=8,-1,[AMG Work Name],[Composer]
Had to add the
~limit=8,-1,[AMG Work Name],[Composer]
to avoid only getting 5 (or 8: decided 8 compositions was better for a week's listening) tracks for compositions that had more than that (e.g., operas) and then had to limit it further with [Composer] after [AMG Work Name] after I was getting multiple compositions called, for example, "Symphony No. 2" (had about 20 of those: I tag from AMG and sometimes pieces have minimal and therefore identical composition names).
Thanks again, Wer, for your help!