This morning when I tested it, I used Open Registry Backup which is the manual Fallback where you have to hit the Backup Now button.
When I've just tried it again and used the Backup Registry Now option, while it seemed to work, the back up in Windows(C: ) only shows the time stamp of this morning's - so I don't know where it has stored that one.
However, using Open Registry Backup option again, the file hasn't changed its time stamp and I think I've updated Adobe Air since then but not sure if that would have made a difference to the file.
Which option did you use ?