Hydrodynamical configuration design is made for a hydrofoil catamaran equipped with a flap system. In spite of the additional elements and the larger hydrofoil area the resistance derived from towing test shows same order of magnitude with the simpler models described in the first report. It is also demonstrated that the use of the flap system extends the speed range of low resistance with high elevation of the hull. The ship motion tests in regular incident waves show that the heave and pitch transfer functions are on the much lower level than the other designs currently used.