An Amagansett development scheme that was met with vehement and nearly unanimous opposition appears headed toward a more than satisfactory solution. A hearing is to be held in Town Hall this evening about whether to use just over $10 million from the community preservation fund to buy the so-called 555 property on Montauk Highway, where a luxury village of some 79 apartments and houses had been planned for those 55 and older. Though specific ideas about how the land will be used are in the formative stage, its preservation for open space and, with any luck, farming, deserve support.