If your #1 engine experiences a surge:
1) Yaw will be to RH side?
No. Number one is the left engine, if it surges it will lose thrust and the thrust from the working engine number two on the right hand side will yaw the aircraft to the left.
2) Pitch down will occur?
No. The Citations have a high thrust line. Increasing power creates a nose down moment, decreasing power or engine surge will pitch the nose upwards. But only very slightly, the effect is not very pronounced.
No. Citations handle very well on one engine, even at low speeds. All pitching and yawing moments asociated with engine failures are easily controlled with yoke and rudder, even without trimming much. Even the much dreaded inflight thrust reverser deployment can be manually controlled by one pilot alone and is trained in the simulator.
4) Increasing PD may occur? (aerodynamic shadow from wings/engines to stab/elevator)
I have not noticed any such effect. But I must say that I fly the C560 non-XL/S. My colleagues who fly both types (560 and 560XL/S) tell me that they behave very similar.