So after a lot of work, the free After Effects script: Auto Crop is now at version 1.0. All of the know inssues have been fixed and some other updates have been made that make this script even more user friendly.
Top Features include:
Automatically crop any nested composition down to the size of its contents
Preform an 'Auto Crop' over time to account for animated layers inside the pre-comp
Crop based on a mask
Crop accurately applies to all instances of the nested composition in the project
Crop can be performed at any time, even if the pre-comp has transform keyframes
Download Auto Crop for free!
See the Video Preview.