Apple has posted an update to DVD Studio Pro through your Mac OS X Software Update:
The DVD Studio Pro 2.0.4 update is strongly recommended for all users of DVD Studio Pro 2. This update adds support for Cropped D-1 and 1/2 D-1 MPEG-2 video resolutions in addition to a number of enhancements and improved overall stability.
Additionally, this update changes the behavior of the dual-layer break point to force a pause during playback of DVD-9 projects while the DVD player switches to the second layer. While this change will increase compatibility of your DVD project with DVD players, you may still use the seamless switch method. For instructions on how to do this, please refer to the following article: http://www.info.apple.com/kbnum/n93514.
For additional information regarding the contents of this update, refer to the DVD Studio Pro Late-Breaking News located in the Help menu or at http://www.info.apple.com/kbnum/n93500.