Not turning pump off when changing valve positions.....bad dog. Just got done typing a response to Mbar about replacing that spider gasket that causes so many problems. You may have caused one or more of the spokes to lift out of its channel and get crunched, thus leaking between ports. But, since it is new you may have lucked out because they are stuck in pretty well but loosen up with age. Try the rinse and see if that cures the problem. One clue to a bad gasket is water coming out the waste line when it shouldn't or when you kill the pump, air leaking back into the system from the waste line and draining water out of the filter and pump. But, that depends on what part of the gasket crunched.
Al