Gingerbread only. If you are on ICS this will not work. Don't try! Get the ICS only tool here: Droid 4 Utility ICS Only
This is based on the original Droid 4 Utility with edits. Contains the complete GB fastboot files to restore your phone, root, unroot, install voodoo rootkeeper, safestrap, etc. Extract after downloading and doubleclick the script to run.
Download here: Droid4 GB Only.zip - 1.19 GB
MD5 checksum posted at the hosting site.
If you have trouble connecting be sure usb debugging is on and you have the latest moto drivers installed. Moto drivers here: https://motorola-global-portal.custhelp.com/app/answers/prod_detail/a_id/78460/p/30,6720,8302
For menu 1 or 2 your phone must be in fastboot mode first. Enter this by using the tool option or manually by powering off, then hold both volume buttons and pressing power for a few seconds, release the power button and select "ap fastboot".
And of course be sure you have a good usb cable and a full battery if restoring your GB system.
Use at your own risk.