Sorry to hear about your troubles guys. I put down a $1000 deposit for an A4 kit but canceled the order after hearing about the problems. So, my loss was only the deposit

Would it be possible to use an electric actuator like this one? A 2" stroke with 15 lbs force. Or maybe it's too slow at 1 sec per 1" travel. It will also need a small 12v battery, but those can be made with lightweight LiPo's

http://www.e-motionllc.com/Mini_elec...ms-15-12-2.htm

There may even be faster actuators available. I just did a quick search.