I am not sure how to trim out the planes. Sometimes it always climbs. It's not the same as trimming a RC plane. Do I do it through the software fsx or the Seitek 52 control software?
Also, when performing missions, I get stuck sometimes against the docks. IS there a way to reverse or do I have to just restart the mission?
The Trim System is designed to trim away unwanted force from the controls(your joy stick) to relieve pilot workload. Some very old aircraft don't even have a trim system. Don't try to fly the aircraft with trim, if your nose attitude is 5 degrees too low than use joy stick(Elevator) to raise it. Once you've gotten the aircraft to the correct attitude, use the elevator trim to relieve the force so that when you release pressure on the stick, the stick will center but the aircraft will stay near the correct position. Trim is not an autopilot and won't hold the aircraft in the correct position for long, it's not designed to. You have to make continuous small inputs to a correctly trimmed aircraft(you must Fly). Elevator trim is used very often and should be assigned(in Flight Simulator with a high repeat rate) to a button that is easily accessible by your flying hand. Any time the Airspeed, Attitude or the Altitude of the aircraft is changed, you have to trim. Aileron trim is almost never used, coming into play only with fuel imbalance or emergency single engine flight. Rudder trim is seldom used, coming into play mostly on high powered, single engine propeller aircraft during long climbs and all multi-engine aircraft during single engine flight.
The seaplane aircrafts don't feature reverse, you would have to restart flight.