Top area displays the current command sequence. If it's empty, press the Q button to queue a sequence.

Top slider changes speed

Second slider is the current position in the sequence

Flip flips the cube 180 degrees.

Command line. Click on the command line to change the sequence. Press Q to queue it up.

Execute command buttons: Rewind, Step Back, Play/Pause, Step Forward, and the last button is currently supposed to be disabled.