It doesn’t work because this plugin was written 5 years ago for bbPress 2.1. The current version of bbPress is 2.5…
The plugin page clearly states it’s been deprecated and then provides instructions on the new and improved method that is supported by bbPress core.
I mean, not work is accurate, I’ll give you that much. But reading the plugin information would have saved you the time and effort of trying out the plugin, being disappointed, leaving a a review, etc.
