We do receive crash reports so hopefully we will be able to identify and fix that issue. With regard to playlists, the new playlist feature which is a single synced playlist across devices has replaced the old multi playlist, device dependant playlist feature. We think this is a much better way of managing your audio since it allows you to access and listen to the same lessons no matter which device/platform you are on. The audio is to have your active lessons in your playlist and to add and remove lessons as you move on.
Just as before, lessons can only be added individually and not by course. Keep in mind that any lessons added to a playlist have their audio downloaded automatically which could be problematic if users accidentally downloaded a long course. The idea again is to have lessons you are actively listening to in your Playlist at any time.
What is it that you would like to be able to do that you are not able to do now?