Following the steps down to the letter I combined 2 videos using PIP. Yet i only see a transparent square that i can move and not a video. i hear the audio form the video but do not see the picture. what do you think is wrong?
iMovie 9 has exhibited that problem when run on El Capitan. It is not entirely compatible with El Capitan. So, if that is your set up you might consider upgrading to iMovie 10.1.2 (latest version) which is designed for El Capitan.
