What part don't you understand? I'm pretty sure that both are explained in all of the basic LabVIEW tutorials but I'll try to help you explain about connector panes and terminals. If you go up to the icon in the upper right corner of a VI, you can right click and select 'Show Connector'. This will display a pattern of boxes. These little boxes are connection points for the VI's terminals and controls. I you move your mouse over the connector pane, it will change to a wire tool. For your Diffser VI, click the box on the left side and then click on your 'e' control. You have now wired a control to the connector pane and it is through the connector pane that a higher level VI can pass data to your subVI. You can then move the mouse back to the connector pane and click on the little box in the upper right corner. Then click on your array called 'Delay'. You have now wired and indicator to the connector pane and and it is through this that the subVI will pass data back to a calling VI. By convention, inputs go on the left side of the connector and outputs go on the right side. There is a whole section in the on-line help under the 'connector panes>assigning terminals' topic.
