I keep receiving the message "Please select button image."
 
      I don't see anywhere that requires me to select a button image when designing the graphic. I'm unable to save the page or continue.
    
 Here's what to do:
- Go to the Design step of your campaign
 - Expand the EDIT WIDGET section
 - If the 'Button' tab is selected, select 'Sticky Tab' and then you can Save & Deploy