The method of storing a time based stream of information to generate a presentation is provided for in which a processing system is used. The methods provide for deleting a selected time based stream of information from the storage medium. In one embodiment, a process manager in the processing system deletes selected information in response to a user selection command. This process manager may further check for reference data to the information and only delete the information is no more than one reference to the selected information exists. A trash depository may be used as an intermediary holding area for the information prior to is deletion. Other aspect of the present invention relating to the processing system conserving storage for a time based stream of information for use in authoring a presentation are also described.