This slip up can be viewed when R2, Qui-gon, Jar-Jar, and Padmedala are wandering toward Mos Espa.

The ILM Crew forgot to brush out the bar that kept R2's Legs together in the sand. Now it is not that noticeable when first are off the ship or initially rolling toward the town, that is up until R2 roles into town, the panning scene with the camera toting little alien bunch, anyway, the bar picks up a bit of Dewback dung and drags it down the road, bet that smell is just murder to get out of astromech...