photos don't show in new retina macbook pro

I migrated my iPhoto library to new MacBook Pro with retina display. It took several minutes to rebuild thumbnails and then it prompted me to rebuild high res thumbnails for retina display or prompt to be reminded later. I went for later. But none of my pictures display. The titles and events are all there and there is an icon for each photo, but it is blank. What do I do to correct?