Your forum link asks for a login, and displays nothing else. See attached screenshot.
The Recent Topics island can be enabled and configure d from the Control Panel. The island settings group are near the bottom of the menu on the left.
In addition, many bugs have been fixed and new features have been added since your installed version, 7.5.8 (2013). I advise upgrading the current software version, 7.6.0 (2017).
