The pilot had little or no previous flight time in this Romanian built glider. He reported departing from an airport located on the lee side of the Sugarbush Mountains. He stated that a strong west wind produced a turbulent rotor near the airport and the surface winds were from the southwest at 10 gusting 20 kts. About 1.5 hrs after takeoff, he encountered significant lift and then a turbulent descent as he was maneuvering to land. While turning final, the lift increased and he used what he thought was the dive brakes. He also slipped the glider, but was still 200 ft too high at the threshold, so he made a 360 degree turn. After the turn, the altitude was still high, so he slipped to the left and right. The glider touched down fast near the departure end of the runway, then overran and hit bushes. The pilot stated that the flap handle was located where the dive brake handle was located in other gliders he had flown. He believed he failed to activate the dive brakes on final.