Dave
when selecting functions you need to make sure that you have at least one led hooked up to your BU. Say for example you want to set the number of shells your tank carries.
What you do is the appropriate first steps, once you are aiming your remote you choose your function button in this case it is the number 8 on your remote. Hit the #8 once, your led attached to the BU will blink a number of times signifying how many shells you can carry. If you hit the #8 again your settings should increase to the next value.
#8 hit once will move your selection to the second value which in this case is 8 rounds of ammo. If you hit the #8 again you change the value to 16 rounds etc etc etc.
With the Clark board the values always increase to the maximum value then they drop back to the minimum value and increase through the scale again.