A public input session is being held in New Milford tonight to gather opinions from residents on what the Lillis Administration Building could be used for in the future.  The 50 East Street facility currently houses the school district's central offices, but it does not meet ADA requirements. The 23,600-square-foot brick building is listed on the State and National Registers of Historic Places.  A consulting firm is putting together a community-based adaptive reuse study, paid for with a State Historic Preservation Office grant.  The meeting is from 6pm to 9pm at the Senior Center.  Options discussed over the years for the building have included selling it to be affordable housing or an assisted living complex, emergency services headquarters or office space.