I just got a Norstar CICS 7.1 with a CLID cartridge and getting Caller ID to work has been a learning experience.
First, your system needs to have CLID capability, and second, you need to turn enable it set by set, and third, select which CO lines it will be shown for (also set by set). These settings are under the "Telco" features under the "Terminals&Sets" menu.
An easy test of the system's capabilty is to have someone external call you, and after you answer on your prime line, see if the CLID is displayed on your set. If it shows after you answer, but not before, your system has the capability and you need it enable it for each set. If not, your system might need an optional cartidge or upgrade.
BTW, anyone know how to get CLID displayed on a SLT with an ATA2? Thanks!