Each time you need to put an image on your game you access the media library
From the image upload page you can either click on the "Click here" button or drag your files from your desktop.
Accepted formats are JPG, PNG and GIF, these files must not exceed 5MB.
You can create a folder and import the images into this folder or import them into the root.
You can also create sub-folders in your folders.
You have several other options on your images. You can rename them, remove them from your space (it will never remove them from your games if they are embedded in them), you can also preview them and group them into folders.
The library is also where you can install your fonts.
You have access to a third tab called "Template" which contains elements you can use for your games. They are sorted by time and you have graphical elements like mechanics but also background or buttons.
You can view what is inside the folder by clicking on it.
If you like the template, you can click on "Import", the complete folder will be placed in your media library.