Glad you are making progress, I was going to ask if you had managed to sort anything out prior to me trying to explain a way to do it but I knew I wouldnt get back on here till later so I figured I should post it anyway. Forgot about deboincing switches.

Looking good so far, I'll be interested to see how you do the targets.
The Xbees, do they not have an antenna ? what is the range on them ? They look much smaller than the wireless thingys I have.

Calv