Rendering Motion Projects for Use in Final Cut Pro
If necessary, you can export a Motion project to a QuickTime movie and import it into
Final Cut Pro. This method is less flexible than importing Motion projects directly into
Final Cut Pro, so you should usually avoid this option. When you export the Motion
project, choose the Animation codec for lossless compression and to include an 8-bit
alpha channel. The alpha channel makes it easy to composite the QuickTime movie
with your footage in Final Cut Pro.