Nissan Navara 2.5-litre diesel vibration

I have noted that another reader has reported the severe vibration/shudder in the auto 2.5-litre diesel Nissan Navara. I understand that this may be caused by the transmission torque converter locking up in an attempt to provide better fuel economy, but it is preventing the transmission from downshifting until the revs drop back to about 1200 rpm or the accelerator is pressed to the floor. Under about 1600-1800 rpm the engine doesn't have enough torque to maintain momentum on anything but flat ground and excessive vibration occurs as the engine struggles on mild inclines or when towing (similar to a manual if you try and hold too high a gear). In traffic or when already doing the speed limit it is not possible to accelerate to force the transmission to shift. Can you let me know if this vibration is likely to cause damage to any aspects of the vehicle over the long term? Also, would the fuel economy actually be better or worse when the engine is labouring at these low revs compared to a free revving engine at about 2000 rpm? I have had the local Nissan dealer look at my car and they advised that there are no adjustments or tweaks that can be made to the transmission. How hard would it be for Nissan Australia to establish new computer settings to change the shift characteristics, i.e. is that something that owners could expect Nissan to be undertaking or is that unrealistic and we are stuck with these poor performers?