my @sorted_date =
  map { [ $_->[1], $_->[0], $_->[2] ] }
  sort { $b->[1] <=> $a->[1] }
  map { my @n = $list{$_} =~ /^(\d+)\.(\d+)\.(\d+):/;
        my $d = sprintf "%02d%02d%02d", @n[2,0,1];
        [join('.',@n), $d, $_] } keys %list;


step 1: build a list of hash keys: keys %list;

step 2: build a new array by:
        for each element of the list built in step 1,
          
          capture the MM, DD and YY values into @n
          with the @ary = $str =~ /pattern/ idiom,
          
          normalize the date into YYMMDD form,

          store the original date, normalized date and
          hash key in anonymous array
       
step 3: do the sort on normalized dates

step 4: just reshuffle the fields in sorted data.