How do I change permissions of "Guest" group in Projects?

CDMS_Project_Team_Coop_(alcateluser2_-_(deleted))

I would like to modify the groups that have access to a project workspace so that people can add items, but cannot checkin/checkout documents. To do this, I would need to change the permissions assigned to a "Guest" group or a "Member" group... can I do this? How?Nick Cristellonicholas.cristello@alcatel.com