Extra Folder Columns

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wót gyc dnja Awg. 20, 2010 · trajny wótkaz

After upgrading to TB3.1.2 I followed the suggestion in installer and installed this add-on, but I don't see anything on my folders' left pane.
I browsed through menus, options, settings and the like and still haven't found a clue of what I should do to have these "extra columns"...
One thing I'd like to have is the progress bar - that now is on the bottom-right corner - in front of each of my account folders displaying for each its own download progression status...