the defrost channel on the back appears to be warped and not tight to the rear panel resulting in water dripping into the channel but as soon as it enters the tube it drips onto the shelf then onto the bottom of the unit and leaks.
Is there a mod for this or can anyone provide a part number for the channel?
Most likely the drain tube is blocked as it will overflow on the small channel from the main drain channel you will have to remove the fridge from the unit then remove the drain pipe to clear the blockage.