Apple has released ProKit 5.1 for Mac OS X 10.5 and 10.6. The upgrade (http://support.apple.com/kb/DL1008) fixes issues with user interface software resources that are shared by Apple’s pro apps.
The issues addressed include: corrected an issue with improper scrolling behavior; resolved memory leaks for improved performance; and addressed layout of interface elements in certain application alert windows. The update is recommended for all users of Final Cut Studio, Final Cut Pro, Motion, Soundtrack Pro, DVD Studio Pro, Aperture, Final Cut Express, Soundtrack, Logic Pro and Logic Express.
The update is 32.39MB. ProKit 5.1 requires Mac OS X 10.5.8 or higher.