Aperture 3.1 edits don't show up in iMovie '11

I am new to Aperture. I am using iMovie to create a movie with still shots that I am pulling in from Aperture. In the photo browser I can select a photo and then click "Open in Aperture". I've done this and edited my photo. But the edits do not show up in iMovie -- even after closing and reopening both programs. Why is iMovie still using the older version of the photo? The weird thing is that some (but not all) of my edited photos now show the edited version in the iMovie thumbnail browser, but when I drag the photo into the project it still shows the old version. HELP! Project due SOON!