I am certainly glad that you found a solution to your problem. I was not quite so lucky. I started LR one morning only to find that my catalogs were nowhere to be found. I had taken alot of time to import my folders that were important to me. Upon searching for the catalogs it was found that they were corrupted, including the backups for some reason.
I had some 14,000 images in the catalog and even support could not help me out on this one. Live and learn. I have a funny feeling it was a power spike that we had here and I now have an UPS. The bummer of the whole thing was that I probably had close to 100 hours worth of keywording done on these.
I have started all over and am now building smaller catalogs.