Not all the fashion action is on the runway. More than 200 fashion houses set up exhibition booths at the fair, attracting some 5,000 buyers over the weekend. Irene Galitzine, the Rome couturier whose palazzo pajamas made fashion history in the 1960's, was one of those surprised by the traffic. She showed two small collections: sportswear with nautical themes and silk or linen dresses. One of the popular styles: a one-shouldered tunic over cuffed white silk calflength pants.