WE HAVE A MANUFACTURED HOME THAT HAS DEVELOPED CRACKS IN THE DRY WALL ON THE CEILING. WE HAD IT REPAIRED ONCE WHERE THE CONTRACTOR SCRAPED THE AREAS, TAPED, RE-POPCORNED AND PAINTED. HOWEVER, SOME OF THE ORIGINAL CRACKS HAVE REAPPEARED AS WELL AS NEW ONES. ANY SUGGESTIONS? THANKS IN ADVANCE