I think you'll get what you want if you change
my @reg= %{ ... };
to
my @reg= keys %{ ... };

Also, $Registry is already provided to you. 

use strict; 
use warnings;

use Win32::TieRegistry;

my @reg = keys %{ $Registry->{"HKEY_CLASSES_ROOT\\batfile\\"} };

for ( @reg )
{
    print "$_\n";
}

[download]

outputs 

DefaultIcon\
shell\
shellex\
\
\EditFlags

[download]

In reply to Re: Windows Registry - printing keys by ikegami
in thread Windows Registry - printing keys by tcf03

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