Architect Santiago Calatrava unveiled a new model of his World Trade Center PATH hub last Friday at the Queen Sofía Spanish Institute on the Upper East Side. Often likened to a white-winged bird taking flight, Calatrava’s design for the train station has faced several cost-saving cutbacks over the years, although the price tag is at about $3.2 billion, about a billion more than the original esimate. In addition to the new model, the exhibit includes the most recent renderings and a multimedia presentation. The exhibit will run through the end of August.