You should let the rudder go once the plane touches down. Worse case, the plane will steer towards the direction the rudder is being held, which will be the correct way to compensate for the cross-wind. You should let go of steering all together once the plane is tracking down the runway correctly, and only feed in minor adjustments to keep it tracking straight. Although the rudder will move once the front wheel is on the ground as you steer, it won't really do anything.