It sounds like everyone has a handle on the problem but I'm not sure I agree with everyone's solution. Keeping in mind that this is a trainer and won't fly inverted with the ease of a sport plane, I think adjusting wing incidence is not the right move. This is a flat-bottomed wing and inherently will be more difficult to fly inverted. I fear that adjusting the incidence for better inverted flight will serve to create a more unstable plane while flying right-side-up. So you adjust the incidence and what happens? Now you have a plane which only flies half-way decent inverted and crappy right-side-up! In my opinion, the best solution is to slowly adjust the C.G. rearward to a point you are comfortable with and dial in as much elevator throw as possible. Good luck!