Dragging and dropping chords from the circle of fifths is completely broken in Cubase 15.
When you try to drag and drop a chord to an instrument track, some chords can’t be dragged at all and others all result in G7b9 being created, instead of the chord that was actually dragged.
When you try to drag and drop them to chord pads, some pads can’t accept the dragged chord at all and other pads change to chords different from the dragged one.
To assign a chord to the next unassigned chord pad, right-click the suggested chord, and select Assign to First Unassigned Pad, or double-click the suggested chord.
You can also drag the suggested chord and drop it on a chord pad.
Confirmed. In C14 all three methods work, in C15 the double-click and drag methods don’t work.