Sorry that I missed to answer your problem, to get the plugin working you just need to place phphpbb before the (.
So it would look like this: phphpbb(‘phpbb_’,’5′,’-#-us-#-un-#-ae posted in -#-ts-#-ti-#-ae-#-br’,’https://myblog.com/discussion/’,’H:i \o\n D jS m.Y’,’Reply on:’,’1′) and this is placed somewhere within the php code.
An example is given within the latest contribution of it you can grab it here: https://phsoftware.de/downloads/wordpress/plugin_phphpbb.zip