The Add Document Window is just a means of associating a document file, such as a spreadsheet, with a booking. It is called from the Add/Update Booking Window. Use the Browse button to select the file and then add a description of document. Click OK to confirm your entry.
When adding a document file to a booking, always remember that access to the document is controlled by the application that created it, and the rights the user has for the computer, drive, and folder where the file is stored. The rights of users to edit or view a specific document are not affected by their rights to view or book resources in ResSched.