This records player input/camera movement and plays it back. Some player actions such as vehicle movement are not supported.
You need to start and record in game mode (Press Ctrl + G in the Editor after the level has been fully loaded, or load the level in Pure Game Mode.
After each playback you get a log printout that looks like the following (in the console and also in the file timedemo.log in the level directory for the level used):
TimeDemo Run 131 Finished.
Play Time: 3.96s, Average FPS: 50.48
Min FPS: 0.63 at frame 117, Max FPS: 69.84 at frame 189
Average Tri/Sec: 14037316, Tri/Frame: 278071
Recorded/Played Tris ratio: 0.99
Ctrl + PrintScreen
Ctrl + Break
Shift + PrintScreen