NOTE: AddRemoveUser cannot be run from the Finder. You must run it from within the Terminal application /Applications/Utilities/Terminal by a user with administrator privileges, as follows:
To add user1, user2 and user3 to group boinc_master, enter the following in the Terminal application:
 sudo {path}/AddRemoveUser -a user1 user2 user3
where {path} is the path to the AddRemoveUser application. This also sets a login item for each specified user so that BOINC Manager will start automatically when that user logs in.
You can also use:
 sudo {path}/AddRemoveUser -s user1 user2 user3
This is the same as the -an option and also sets BOINC as the screensaver for the specified users.
To remove user1, user2 and user3 from group boinc_master, enter the following in the Terminal application:
 sudo {path}/AddRemoveUser -r user1 user2 user3
This also removes the BOINCManager login item for each specified user. If any of the specified users had BOINC set as their screensaver, it will change their screensaver to Flurry.