This feature is a great timesaver. Now you shouldn't run new preset each time you want to view a generated image. Each frame of the presets sequence is a thumbnail of your generated picture (New Image mode) or loaded image with an effect applied (Open Image File mode). You can simply look at the presets sequence to see the final result. So you can easily choose an effect you like, and after that generate the image or add it to your photo, by running this preset.
WARNING! In the Open Image File mode a loaded image will be a background for a generated image only for the presets with the Background color checkbox disabled.
For your convenience, the presets are splitted to thematical galleries. They are located at the bottom left of the main window as a list of categories. There is a numder of presets in gallery shown in round brackets next to a gallery name. You can create new galleries, edit and remove them, and change the position of a gallery in the list. If all categories can not be shown in the Galleries panel, use the scroll slider to get an access to the galleries you need at this moment.