You can access the Cover Page Image button in the Reports tab to set an image for the cover page and Proposal reports specifically for the project.
Click the Cover Page Image button, and the following interface opens.
The following are the options on the interface.
Use the cover page and proposal image from the global report settings
This is the default, and this option will use whatever image you have uploaded under Report Settings in the Control Panel.
Use specific cover page and proposal report image in this project
This option will allow you to add an image specifically for the project.
This image is stored in the Project folder automatically and is displayed in the Files tab in the Project Explorer.