From 1.9.4 > this feature become option on plugin admin page.

Activate integration without linking users between WordPress and phpBB

It is possible to display Last Topics Widgets and Shortcodes to display phpBB Last Posts or Posts contents into WordPress Pages/Posts. It is also possible to use the template integration to display the phpBB forum into a WordPress page (also cross domain).

The plugin can be used in this state also to transfer/migrate users between phpBB and WordPress or viceversa.