when trying to remove a song from a setlist...
That's the intended behaviour. Removing a song from a group does not delete the song
The only place where you can actually delete a chart from the library is from within the 'Songs' tab.
You can also do it on the recent tab and one of the groups tab if you tap the overflow menu at the top right and select the option for "Delete Song from Library".
No, what I am saying is it does not remove the song from the PLAYLIST! I do not want to remove from the library.
To clarify, this is the action where you long press the title select edit and then select remove (top right hand).
Both that one and the one in the overflow work for me [long press song in the setlist, then press 'remove' at the top or in the overflow, not in edit].