When I'm attempting to import video, the files don't show up, just a black "loading" icon. Then one-by-one, as the software is trying to read the camera, the files disappear. Once the IMPORT ALL button is Green, all the files are gone and the import screen closes.
Just updated with latest El Capitan system upgrade and running iMovie 10.1.1
iMac, OS X El Capitan (10.11.4), 2.66 GHz Intel Core 2 Duo, 500 GB