Hi Philco,
Welcome to the airsoft club of Clark madness. I thought it was just me but as you say, the instructions are not good enough. Now, I have been doing some more research and have established (I think) that to make the Clark board work properly with airsoft, you need to make sure that your airsoft gun has the microswitch fitted to the back of it. the board will use this switch as a signal to recoil the tank and thus initialise the cannon sound etc. I've yet to try this as I have been short on time but I'll have a go over the xmas break and will post further.
cheers
CaptB