The Image Uploader is built into the Genesis Extender Plugin to make it easier to incorporate images into custom CSS, specifically using the Front End CSS builder. Upload the image using the Genesis Extender Image Uploader and the image is available for use with the CSS Builder and the Front End CSS Builder.
By default images are uploaded either to the following directory:
But in a WP Multisite situation they will be uploaded to the following directory:
(Note that the number "1" in the above /wp-content/... directory is only an example of a possible BLOG ID.)