You can preview your compilation and edit (scale, rotate) clips in the preview area in the upper left of the Video Editing screen. Shift the current position by dragging the timeline slider on the time scale.    
The following setting options are available in the preview area:
Button
Switches to full screen mode. 
A control panel is displayed in the lower area of the full screen. To return to window mode, press the Esc key on your keyboard.
Drop-down menu
Show
Displays the selected editing tools: You can choose to display rulers, guide lines, as well as a safe area which marks the outer 10 percent of the total menu width and height as protected from title editing and the outer 5 percent of the total menu width and height as generally protected. 
The Snap to guide tool sets the clip to the guide if you come near a guide. The Snap to object tool sets clips to each other if you come at 10 pixels to the snap line of an object with another one. Snap lines are left, right, bottom, top, horizontal center, and vertical center of both clips.  
Button
Creates a snapshot of the displayed position in the video title. 
Button
Jumps to the next or previous edit (from all tracks).
Button
Jumps to the next or previous frame.
Button
Stops the playback of the movie.
Button
Begins/pauses the playback of the movie. 
Jog wheel
Navigates through the project on a frame-by-frame basis.
 
See also
Video Editing Screen


Preview Area