After recent upgrade, missing images

Question

I allowed the Aperture upgrade to go through. New Aperture upgraded the library. The upgrade was not going through (stuck on step 6), so after searching on the web, I started Aperture with Cmd-Option key. I chose the Rebuild library option and that needed upgrade also, and the upgrade happened.
Now, I cannot see images in projects created over the last two years. The images are in Aperture I can tell - because in Library>Projects I can see all the images. However, if I chose a project in left panel, the project has zero images. If I navigate to Library>Photos, then no photos from last two years can be seen. The search box however shows "showing all" photos - so there does not appear to be an obvious filter on.
All processing, creating of previews, thumbnails, face detection post the library build has happened. Since then I have fixed permissions, repaired library, and again rebuilt library.
The images are definitely there - because I can see the images in the referenced location where I stored them.
Here are some snapshots of what I am facing.
One project in Library>Projects
This one has photos. But this is how I view it in the left panel.
There are other threads with this problem, but I thought that if I elaborate, then maybe some of you can pinpoint the specific problem that I am facing.
Thank you!

Answer 1

If rebuilding the database does not work, and you have no backup of the Library from the time before the upgrade, you might try this:
Make a backup of your Aperture Library - an exact copy on disk with enough space.
Look at the projects with missing images and take not of the time these  projects have been imported. 
Then ctrl-click he Aperture Library package and look inside by selecting "Show Package Contents" - look into the "Masters" folder. Your original image files should be stored there, files away by import date.
Do you see your images inside? If your original images are still there, you now have two options:
Create a new, empty library and import the original masters (for the missing images) from the "Masters" folder into this new Library. After checking if everything is o.k. import this into your other Library.
Or try to manually fix the other library by removing the database files from within the package.
To manually repair the library, if rebuild does not work:
Caution, caution, caution:
There is one one last desperate method to save some parts of your library that you might try - but that might wreck the library completely, so you need to make sure you have a backup copy before you even think about trying this:
To manually repair a library see here:
      Re: Aperture 3 rebuild library - SQLITE MISUSE
Frank Caggiano wrote about this method not long ago:
That's really the option of last resort it is way to easy to totally wreck the library doing this.
It's like the sign over the gates in the Inferno:
Abandon all hope yee that enter here!
I wouldn't advice to try that, unless seeing you are about to recreate the library completely from scratch.