Don't you see them in the members list in the game client? They are sortable there!
The remaining title besides the common member is recruit, the only functional title IMHO. It's assigned to each new member automatically at CC entry but may be given or altered deliberately by the owner.
None of them has any role, and nothing has been published AFAIS. Therefore, I did not assign any director until now.
As an owner, I appreciate "recruit" which makes it easier to spot if they are perhaps mayflys, and I assigned it to a few passive members (last game 2013) to ease further selection when I need space in the future.
A few passive Masters and TMs received "veteran" for the same purpose.
Edited.