Since gerrit was put to read-only mode, searches by keywords cannot be done . The Download menu previously displayed to checkout a given Change-Id is no longer available, and I did not succeed in guessing the appropriate gerrit repository URL for checkout, e.g.
For some weird reason, Firefox was not allowing me to download the .diff file. I was able to do it using Chrome.
But thanks for providing the link, and for providing an explanation that can be helpful for other fellows that may want to pick up some of the unfinished work form gerrit .
The additional git diff patch application steps were also appreciated.