What type of file are you trying to load? The easiest way is to past a youtube URL.
Click create new gallery and a pop-up box opens. You have to name the gallery, and you also pick which type of gallery (lightbox, space gallery, etc) that you want to use to display your videos. Click add video, and it will open another pop-up box. You have to give your video a title and either upload your video file, or past in the URL of the video. Then you click save video. You do the same thing for each video you want to add into the gallery. When you have your videos added, you just click save at the top of the gallery box and it saves your gallery. Inside your gallery, you will see a short code like
total_soft_gallery_video_id=”1″
You just copy that code and paste it into whatever page you are wanting the gallery on
Hope that helps