When you start the animation process, the first action is assigned to the first step of the first sequence. If this sequence is active and the current time is at the end of the first step, the next action is assigned to a new step of the sequence. If the sequence is not active, the next action is assigned to a new step in a new sequence at the same current time. The next action is also assigned to a new step in a new sequence if the current time has been set to an unoccupied section. This applies irrespective of whether a sequence is active.