Bob-O is right that the Bcat Composite will climb when dropping the gear with excess speed. As for the elevator, you definitely need up elevator mix as per the BVM manual when flaps go down. I'd suggest that you use the numbers in the manual and adjust as needed. If it is flying too slowly in the landing pattern with flaps down, take out a point or two of up elevator mix. If it is flying too fast in the landing pattern with flaps down, add in a point or two of up elevator mix. If the plane initially balloons excessively on flap deployment and then settles down, you may be deploying flaps with excess air speed. This is my experience with the Bcat, FWIW.