I don't recall needing root in order to unlock the bootloader. No mention of root requirement in the first post: http://forum.xda-developers.com/show....php?t=2226504.
1. Extract the entire contents of the zip file.
2. If you are using Windows, ensure you have installed the latest Motorola USB drivers available for your phone.
3. Ensure your device has been rooted and you have a working installation of “su”.
4. Ensure USB Debugging mode is enabled on your device.
5. If you are using Windows, navigate to the extracted directory and execute “run.bat”. If you are using Linux or OS X, navigate to the extracted directory in a terminal and execute “./run.sh”.
Try doing a search on saferoot. Once successfully rooted, try unlocking your bootloader again.
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