Hi,
Just an FYI for anyone else who may experience high CPU usage after running the iFuntastic ringtone hacking application. I ran it using my MBP, successfully.
I noticed that the machine was running very hot over the next day or so. I checked activity monitor and found two instances of iphoneinterface running and eating up ~ 80% of my cpu. Killed the processes and all is well.
I hope this helps others.
cheers