Another example for sequences

if instance_exists(sequenceTest)
{

    switch (global.currentBox)
    {

            case 0:
            break;

            case 1:
                disableCameraMovement(true)
                if obj_player.y>0           {obj_player.y-=4; obj_player.sprite_index=global.downSprite; sequenceStart()}
                if obj_player.y<=0      {obj_player.sprite_index=global.downIdleSprite; sequenceEnd()}
            break;

            case 2:

            break;

            case 3:

            break;

    }

}