Colette Donovan, Merrimacport, Mass. Where floor plans are concerned, it is the rare antiques show that deviates from the norm. Most are as regular as a grid painting by Mondrian, who had Manhattan traffic in mind when he created “Broadway Boogie Woogie.” Show managers likewise envision customers cruising like yellow cabs down one aisle and up the next. Barn Star Productions chief Frank Gaglio got a lesson in living off the grid after learning that his flagship Mid*Week in Manchester, August 5 and 6, was losing its venue of 15 years, the Wayfarer Inn in Bedford, N.H. The news sent the Rhinebeck, N.Y., promoter on an epic search for a new home for Mid*Week and its companion, the Pickers Market. Eager to keep Barn Star in town, Manchester’s mayor dispatched a car and driver to help Gaglio in his often dispiriting hunt. The breakthrough came in the 11th hour. A local hotelier encouraged Gaglio to check out the Furniture World Building, a vast and empty former showroom in the heart of Manchester’s big box retail district. The rental turned out to be a godsend: big, spacious and fully air-conditioned; easy to find; supremely convenient to reach by car; equipped with a comfortable catering space; easy to set up; and plentifully supplied with nearby hotels and parking. Taking on the Furniture World Building forced Gaglio to think outside of the box. Furniture World is permanently fitted with irregularly shaped alcoves, some with ersatz touches such as fireplaces and beams, the residue of room-set vignettes past. A grid-shaped floor plan was impossible, so Gaglio got to work designing a show to take advantage of the existing architecture. A Bird in Hand, Florham Park, N.Y. Exhibitors rose to the creative challenge, as well. Maryland dealer Lisa McAllister provocatively displayed a harvest table on a sharp angle, while North Carolina dealers Steve and Lorraine Marshall used the rustic, primitive feeling of their space to its best, incorporating early smalls in abundance and hanging a one-drawer Virginia paneled hanging cupboard in original blue paint. “It was one of the most interesting shows I’ve done, unlike…