Cannot view videos in Dropbox bc folder on iMac or iPad. Same videos play properly from Dropbox Public folder. With a "plain vanilla" 30-second MP4 file in bc, for example, the iMac error msg is: "The movie's file format is not supported." On the iPad, the video never finishes loading. Both platforms play the same video flawlessly from the Public folder. Ditto with .avi and other formats. All of these videos play properly from bc in Windows.