Weird. I started with the DropDownHotspots and no dice. Moved on to the DropDownHeads . No dice.
So I deleted a bunch of stuff. I started again and tried manipulating the hotspots again, as suggested. I had to manually enter the class in the HTML (not from the WYSIWYG). I think that's why I was ...
I've read a few forum entries (such as: https://forums.madcapsoftware.com/viewtopic.php?f=6&t=21872&p=111083&hilit=drop+down#p111083) about drop-downs and creating a different style for different drop-down headings. None of them have solved this problem for me.