Space bar 1 time =point shell, space bar 1 more time =fire shell. Change the speed by sliding the "Shell speed" thing. In the red circle is how you get/place the amour. Hold "A" then click the object in side the red circle to change the amour type, click and it will make a copy and follow your mouse until you press "G", use the arrow keys to rotate it. Hovering over a part and pressing P deletes the part touching the mouse. Pressing "1" can change the shell type. HE=explosion and AP goes through amour HE lets you set the timer for when HE explodes
All by me