BuddyPress.org

The default view for the member directory is “active members”. This will only show users who have logged in since you activated BuddyPress, and are therefore considered active (last_activity meta is present). If you change the ordering to something else, the members will show.

Technically this comes down to if a user’s “last_activity” record is present in wp_usermeta. I suppose you could pre-prime the last_activity record by something like this: http://buddypress.pastebin.com/USrLFAFH It’s not tested, but I think you could put it in your functions.php. Remember to remove it after one execution, however(!)