As for Arthur Honegger, this should not be a closet thing anymore since I've recorded his film music on 4 CDs long ago, and that sold very well. 2 voluems vere reissued not long ago. I don't learn all that from royalties received (Marco Polo never pays such a thing), but I look at the composer's rights lists and those from our performer's society and radio performances.
Regards from Switzerland
Regards from Switzerland