Apply a Transition to Individual or All Slides
OpenOffice Impress differs from other presentation software in applying transitions to the slides. In OpenOffice Impress, when you select a slide transition, it is automatically applied to the current slide, or group of selected slides. You do not need to click on an Apply button, as in other software programs.
To apply the same transition to all the slides in the presentation, click on the Apply to All Slides button in the slide transition task pane.