Unless you tell it to do otherwise, Worldox always opens the Full List document tab. In effect, that means the worklist fills up the right-side of the Worldox window top to bottom; there is no document tab open beneath the list.
You can set another document tab as the default choice. Just right-click on the document tab you would prefer to see, then select Set as Default Tab from the right-click menu.
From that point on, the selected tab opens automatically whenever you are viewing worklists.