In Harvard Graphics, I am pretty sure it was used with the "Scroll" transition in slide shows. That option is visible in at 15.34 in your video for the "Euromap

In Harvard Graphics, I am pretty sure it was used with the "Scroll" transition in slide shows. That option is visible in at 15.34 in your video for the "Euromap.cht". As I remember, it only ran smoothly (i.e. used the smooth scrolling registers) in 640x350.