For those battling with nuked/bricked 9900/9930's
For those who are struggling with getting the timing right in order to reload the OS...
Step 1. Download and install the latest version of BB Hybrid Tools.
Step 2. Ensure that the OS of your choice is installed and make sure that no other OS installation folders exist under Program files\Common file\Research In Motion\Shared.
Step 3. Remove the battery (if not already removed) and re-insert it. Wait till the 507 message appears and connect the USB cable. Wait for the Windows notification sounds and open BB Hybrid Tools.
Step 4. Navigate to Shrink an OS and ensure the OS of your choice and phone model is selected at the top.
Step 5. Click on launch loader under the shrink an OS tab. This will open the app loader application but your device and PIN will have been recognised already and you can click next and proceed to installing the OS.
This removes the frustration of getting the timing right while having the battery removed and then replacing it. The above procedure worked for me and hope it helps my fellow forumers.
Give it a try and report back.
Thanks.