Event is created but photos are not in it

Question

I recently put iPhoto11 on my husband's Mac. I saved the library then uninstalled it from my old Mac. I didn't have any problems putting the old library into the new computer but it coincided with the last update. I'm not sure if the problem is with the update or with the new installation.
I download photos from my SD card. It creates an event and they show up in "last import". Then I click on the event (which will say under the key photo how many photos there are) and when in the event it says "there are no photos". They are all gone. I go back out and there is my key photo with the number of photos that are supposed to be in that event but they are not in there. The photos will show up in the library temporarily, as well as last import and I have tried adding them to albums, but if I log out of iPhoto then log back in the event is gone and so are all the photos I just downloaded. They are not in the albums I put them in or in "last import".
Where do I begin to troubleshoot?

Answer 1

Option 1
Back Up and try rebuild the library: hold down the command and option (or alt) keys while launching iPhoto. Use the resulting dialogue to rebuild. Choose to Rebuild iPhoto Library Database from automatic backup.
If that fails:
Option 2
Download iPhoto Library Manager and use its rebuild function. This will create a new library based on data in the albumdata.xml file. Not everything will be brought over - no slideshows, books or calendars, for instance - but it should get all your albums and keywords back.
Because this process creates an entirely new library and leaves your old one untouched, it is non-destructive, and if you're not happy with the results you can simply return to your old one. .
Regards
TD