To change the update interval go into the ACP and either type "live update" into search or navigate to Options > Performance. Change the "Live Update Interval" option to your desired update interval (in seconds).
The error is that the Listener.php is still included and it doesn't need to be.
The listeners were there for template hooks. The add-on uses template modifications since version 3.0. If you want to maintain compatibility with XF < 1.2.0 you need to download version 2.0.