bbPress.org

I’m too silly, damn. This is over my intelligence.
I have the problem, that the posts have the wrong post_parent, so that two topics are merged curiously.

For example Post ID 9257 from the WBB board is attached to Thread ID 9257 from the old board, and I cannot see what I have to change. Please please help!
This took me now over 2 hours changing things and I haven’t found it. I guess it is this part, but I have no idea what to change:

// Parent Post ID.
		// Note: We join the posts table because this needs to be the fist post of a topic.
		$this->field_map[] = array(
			'from_tablename'  => 'wbb1_1_thread',
			'from_fieldname'  => 'firstPostID',
			'join_tablename'  => 'wbb1_1_post',
			'join_type'       => 'INNER',
			'join_expression' => 'USING (threadID) WHERE wbb1_1_thread.threadID = wbb1_1_post.threadID',
			'to_type'         => 'reply',
			'to_fieldname'    => 'post_parent',
		);
		

I updated the wbb.txt above (where I also linked the WBB database structure).