iPhoto crashes while generating high resolution thumbnails.

I have moved my iPhoto library from my old MBP (running Lion and iPhoto 9.3.2). When I started up iPhoto on the new MBP (retina screen), I got the message saying that iPhoto needed to generate high resolution thumbnails. Every time I try to do this, iPhoto crashes somewhere in the middle of the process. After several attempts, I opted to select "Remind me later." Once the app started, I selected "Generate high resolution thumbnails" in the Photos dropdown menu. Nothing happened, and the thumbnails looked very good anyway, so I decided to declare victory and move on.

That was yesterday. Today I upgraded to iPhoto 9.4, and after the app upgraded my library, I got the same ...needs to generate high resolution... message. Same result: app crashes in the middle of the process.

In the process of moving my library from Lion/iPhoto 9.3.2 to Mountain Lion/iPhoto 9.3.2, I had other problems that I resolved through a series of repairs and rebuilds (using Option+Command while opening the app). My pictures look great, the library seems to be in good shape, and I'm not so sure that I DON'T have high resolution thumbnails. So the crashing problem is a puzzler. Anyone have insights on this particular problem.