The 3d title text tool freezes the computer and quits out of final cut nearly every time it is used. It would work 50% of the time when we were using OS9 but now on Leopard it never works. We are on version 5.1 for graffiti and version 6.01 for FCP.
I would like to suggest that you upgrade the FCP and Graffiti software to the latest versions (both are free upgrades for you) and try it again. If you're still having trouble after that we'll bring this into tech support to see if they can offer any assistance in diagnosing the issue.