The Borders Bookstore at the Airport Square Shopping Center, on Route 309 in Montgomery Township, has survived a scare. On Thursday the company released a list of 28 more stores that are closing, and Airport Square was on the list.  Then on Friday the company said the landlord came back and re-negotiated the lease, so the store was taken off the list.  It had been targeted for closing in late May.  The company is still closing its Middletown and King of Prussia Superstores, where clearance sales started last month.  They will close by the end of April.  Borders filed for Chapter Eleven bankruptcy protection in February citing internet competition, heavy debt, cautious consumer spending and a lack of capital resources.  It hopes to emerge from bankruptcy by late summer or early fall as a smaller, but profitable, company.