HI ROB,
Answer your question about the CG........... I am at 4 3/4 from the leading edge at the top wing.I feel that i might be nose heavy.I have a 2700 maph battery verry close to the front.Nose heavy might be your thrust line with the motor.Have you any downthrust?? Sounds to me that you might have a bucket full of wiggeling Worms on your hands.LOL.work on the thrust of the motor mate.... and a little right can be helpful too.Let me know what you done and how it flew.Hope to catch you soon and lets touch some wings.
Willi