27. A system for editing a multimedia presentation that includes a sequence of visual displays, the multimedia presentation being defined by a presentation script such as a presentation script including instructions that include identification of a plurality of content assets, identification of one or more visual displays in which the identified content assets are to be included, one or more modifications of the content assets to be performed prior to inclusion of the identified contents asset in the one or more visual displays, instructions for positioning the modified content assets in the one or more visual displays, and layering instructions for determining, for a portion of the visual display that includes plurality of modified content assets, the forward and backward relation of the plurality of modified assets to each other in the visual display, the system comprising: a processor configured to implement a user interface for editing a content asset for a multimedia presentation, comprising: a bounding box around a display of the content asset, the bounding box including asset editing buttons that cause modifications to a presentation script to accomplish asset editing functions associated with the asset editing buttons.
31. The system of claim 27 , wherein the asset editing buttons include a flip horizontal button.