I tried it like this, and it works. BAILOUT is doable. I designed it to have failing tests just to see what happens...

#!/usr/bin/perl

use strict;
use warnings;
use Test::Builder;
use Test::More;

BEGIN { 
        use_ok( 'Test::Simple ' ); 
}

my $Exit_Code;
BEGIN {
        *CORE::GLOBAL::exit = sub { $Exit_Code = shift; };
}

my $output;
my $TB = Test::More->builder;
$TB->output(\$output);

my $Test = Test::Builder->create;
$Test->level(0);

$Test->plan(tests => 3);
plan tests => 1;

$Test->is_eq( $output, <<'OUT' );
1..3
Bail out!  Sayonara!
OUT

if ($Test) {
      $Test->is_eq( $Exit_Code, 255 );
      $Test->ok( $Test->can("BAILOUT"), "Backwards compat" );
}
else {
     BAILOUT(print  "Sayonara!\n");
}
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