Earlier today I copied my iPhoto library file and the iPhoto prefs file to from my Mac Pro to my MacBook (using Chronosync's "mirror" option), for a week away from home. I've now come to using iPhoto on my MacBook, and noticed that the thumbnails for my modified pictures had reverted to thumbnails of the originals. Clicking on any of these modified images just brings up a large exclamation mark on a grey circle background. I know that this normally means that iPhoto cannot find the relevant file in the library (usually because someone's been messing around in the library - which I haven't; I took a mirror image), but the odd thing is if I click on "Edit", the image I'm then presented with is the modified image, so it's still there and iPhoto damn well knows it. I've tried opening iPhoto with alt-opt to get it to rebuild everything, but it hasn't made any difference. Any suggestions please?