anchor.diff:    BaseOffset = OrigOffset - BackOffset,
     {ok, Type, Base} = unpack_object(F, BaseOffset, Index),
   
  -  Delta = read_zip_from_file(F, Offset + Shift, Size, Bin),
  +  Delta = read_zip_from_file(F, Offset + Shift + size(Bin), Size, Bin),
   
     {ok, Type, patch_delta(Base, Delta)}.
   
  
positive.code:     {ok, Type_, C} = read_delta_from_file(P, Offset, Offset + HeaderSize, Type1, Size, Index),
      {ok, Type_, C};
    true ->
      C = read_zip_from_file(P, Offset+4096, Size, Bin),
      {ok, Type1, C}
    end,
    {ok, Type, Content}.
  
negative.code: 
  
  unpack_object(P, Offset, Index) ->
    ReadAhead = 4096,
    {ok, HeaderSize, TypeInt, Size, Bin} = case file:pread(P, Offset, ReadAhead) of
      {ok, <<0:1, T:3, Size1:4, Bin_/binary>>} ->
        {ok, 1, T, Size1, Bin_};
      {ok, <<1:1, T:3, Size1:4, 0:1, Size2:7, Bin_/binary>>} ->
  