HUGE LOFTS IN KINGS CROSS 'FITTED' OR AS 'SHELLS!'.  Loft living is rapidly gaining a select popularity in central London.  The opportunity to live in a large converted industrial space has existed here since the 1970's - but only on a very limited scale.  The views from York Central are uncompromisingly urban, framed by new floor-to-ceiling double glazed windows.  Trains flow in and out of Kings's Cross against a backdrop of huge gas cylinders and a largely commercial skyline, and much of the rest is commuters, road traffic and goods yards.  The York Central Lofts are sold as shells with sandblasted finishes and mains services.  But there is a fit-out option for the lofts on the first and second floors.  It is anticipated that the lofts on the upper floors, which are only available as shells, will be completed to a very high standard by their new owners.