bbPress.org

‘techy’ fix: (requires php experience)

the bbp_has_topics() function appears to function almost exactly like the wordpress loop.

In the bbpress plugin folder /bbp-includes/bbp-topic-template.php line 68 is the bbp_has_topics function.

It takes the parameter post_parent which you can assign as the id of the forum you are trying to pull posts from. There are also a number of other parameters you can set as well.

‘non-techy’ fix: someday I am guessing there will be a widget available which will let you make the filters with a gui.