Under the Advanced Settings for FooGallery Free, you have various custom and advanced settings. When it comes to using the Custom Settings and Attributes, we recommend that only developers should do this.
From this page you can also add a custom gallery class and enable/disable the Image Title Attribute.
Lazy Loading allows images to load only when a user scrolls down to them. It is beneficial for data use and page load speed, so it is recommended that you use it. It is set to Enable Lazy Loading as the default. However, should you not want to use it, you can select Disable Lazy Loading.