If you are looking to change the number of rings that Unity waits before pulling a supervise-transfered call back, it's on the transfer page for a subscriber. This setting works for calls that are in Unity, the caller dials the number of some one's phone, and Unity transfers the caller to that phone.

That's different from the setting that controls how many rings will a phone ring before it forwards some where. This setting would affect if some one were to call a phone directly. That is controlled on CCM, and I thought that it was a system-wide setting but I don't know for sure.

Forwarding and transferring are two different things that are often confused.