Yes. Go to Messages, click Manage Images. Mustang List has created an Image Directory for you, entitled Top Level. It is a good idea to places images common to all messages, such as company logos, in the Top-Level directory.

Store images used for a specific mailing in a directory that relates to the mailing: for example, a directory named "20060801" could hold images used in a mailing sent August 1, 2006. This will help you quickly find the image files if there are any problems with them or if you’d like to re-use them.