Video titles show in playlist, but no video - just blank white squares

I got Shotcut today and started watching tutorials. I can drag a video to the playlist, but there’s no video - just blank white box with a file name. I cannot open the video. If I “open file,” a video will play in the monitor OK, with the properties showing, but nothing is retained in the playlist. I’m using a Mac with El Capitan. Also, there’s no encode option anywhere, like in the first Shotcut tutorial. thanks

I just downloaded it again and the problem appears to be gone. False alarm.