Navara D40 Clutch Problem

Took for the D40 out yesterday for a bit of off roading. Ended up in some rough stuff, engaged 4 low and tried to reverse out. Clutch pedal all the way out( and I mean all the way out), engine powered up and the beast never budged an inch. I think the front left hand wheel may have been clear of the ground as well at the time? There was that acrid smell of burning clutch, so I stopped the process and tried to go foward. Eventually got out of the fix, but the clutch did not to handle the situation well at all. Only 12,000klm on the vehicle and only the second time I have used 4 low.

The conditions I was in, were not extreme at all, which concerns me. It took well over and hour before the smell of the burnt clutch disappered.

Any other D40 owners or Nissan mechanics out there, who have had or come across similiar problems, with their clutches in similiar circumstances?

Regards,

Macca