Gian,

Better test of correct CG- take the plane up, and put it into a 45 degree dive. Let go of all controls, if the dive steepens, you are tail heavy, if the plane pulls up out of the dive you are nose heavy, if it continues on the path you set it on, it's balance pretty close.
I know this may sound backwards, but it's not.

Also, for your spins, try (after you get it going) feed in OPPISITE aileron, and full throttle, this will flatten the spin considerably, and makes it more interesting.
Keep pushing the envelope!!!!!!!!!!



Jetts