I have a similar issue with the x-55 - the leading edge is acting like elevator - you push forward on the stick (yoke) and the leading edge flaps extend fully, pull back on the stick, they retract - something is wrong with the 737 and x-55 stick. Major bugs with all the stock heavy metal.
Also, the 737 performance is no accurate, takes almost 10,000 feet of runway to take off, then the aircraft only climbs at 200/ft/min? Please fix these jets, they are not airworthy.