I found a copy of that Evil Gnome video on YouTube. Here it is for your viewing pleasure:
I’m still trying to figure out what the thing is. I don’t buy into the notion that it’s a viral marketing gimmick; I think if it were it would be of better quality. I’m still of the opinion that it’s a genuine video (as in a video shot by some random guys instead of a viral marketing company), just not a video of a creepy gnome like creature lurking around a town in Argentina. Judging by the nearby foliage, I’m thinking the critter looks to be about a foot tall, which rules out even the shortest primordial dwarf. My best guess at this point is that it’s some sort of small monkey. I’d even consider the possibility that if it is a monkey, someone might have dressed it up in some weird outfit. I’m just about 99% sure it’s not a supernatural critter of any sort.