After being renovated for mucho tiempo, the Mexican restaurant on Fifth Avenue between 12th and 13th streets has finally opened. Piramide, which is in the large space next to Commonwealth, is a fancier than usual south of the border eatery that purports to serve modern interpretations of traditional Mexican food. The menu offers entrees like carne asada and salmon seasoned with avocado salsa (both $18). Although the restaurant is up and running, it won’t have an official grand opening until October 19th, which is when its owners expect the city to issue them a booze license. Wares untested, the joint’s already left a bad taste in the mouth of a couple of folks on a Brooklynian thread who say that it has an uninviting vibe because its employees are constantly on smoke breaks. Anyone have a report on the chow? GMAP