The 'Home' and 'End' keys will jump to the beginning or end.
A full list of available keyboard shortcuts can be found here.
Playback- Keyboard Shortcuts
Playback controls are in the main player interface but can also be accessed via shortcut keys.
You can use the space bar to play/pause playback, and the keys J, K, and L can be used to play the clip backward, stop, or play forwards.
Playback options (looping and ping pong[moving back and forth] can be toggled on and off, either by using the Once/Loop/Ping Pong button to the side of the play controls, using the Playback function in the 'Navigate' menu or by using the shortcuts.
'In' and 'Out' Points can be set to define the start and end of a looped section - again, this can be set in the 'Navigate' menu, or via the shortcut keys I (set In point), O (set Out point) and C (Clear in/out points).
You can also jump (or 'scrub') to a frame by clicking anywhere on the timeline - cineSync 5 will jump immediately to that position, and everyone in the review will be placed in the same position.