[Vierie]

You could try this hack: https://vborg.vbsupport.ru/showthread.php?t=83230

You would have to change the xml-file a bit.

Find:

PHP Code:

 // fetch the permissions for each forum
     global $vbulletin;
     $forumperms = array(); 


Below add:

PHP Code:

   $limitfids = x; 


x would be the ID of the forum, from which you want to have the threads displayed.

Find:

PHP Code:

// ## HIDE FORUMS WITHOUT THE CANVIEW PERMISSION ##
      if (!($forumperms[$forum["forumid"]] & $vbulletin->bf_ugp_forumpermissions['canview']) AND !$vbulletin->options['showprivateforums']) {
          $limitfids .= ','.$forum['forumid'];
      } 


Remove it.

Find:

PHP Code:

AND forumid NOT IN (0$limitfids) 


Change to:

PHP Code:

AND forumid IN (0$limitfids) 


If I didn't forget something critical that should work, but give me some feedback.