Thumbnails never get created -- any idea why?

Thumbnails used to get created--although sluggishly--until a couple of SpeedDial versions earlier. Now all dials display the circling dots forever, thumbnails are not created

Slimjet browser and Comodo Internet Security Premium on Wndows 7 Ultimate English x64. No changes made to the system or setup since the last time SpeedDial thumbnails were created.

Love SpeedDial, I'd hate to have to give up on it.