Cougar,
That nose-down tendancy with your plane is no big deal.

Short coupled planes tend to nose-down when flaps are dropped, while planes with a longer tail moment will pitch up. It's possible to get a plane with just the right combination of CG, tail length and size, flap size and deflection etc etc, that it won't pitch at all when you hit the flaps.

So, when trying flaps for the first time, be sure to do it up high. It's hard to predict exactly what the effect will be on a given plane.