RegistryUI settings can only be managed by an administrator.
The Registry > Settings page is used to configure RegistryUI.
The Logo tab is used to define the optional logo displayed on every page (top/left corner). This is typically used to display your company logo, particularly for a public registry. The best image size is around 160 x 60 pixels but there is no exact size requirement. The image will be shown in its original size. If the image is cleared, the default product logo is used.