I think you want

 use if $^O eq 'MSWin32', 'Win32::OLE', 'CP' => 'CP_UTF8';
[download]

That is still the "old" way of using Win32::OLE. The new way would be something like:

use if $^O eq 'MSWin32', 'Win32::OLE';

if( $^O eq 'MSWin32' ) {
    Win32::OLE->Options( CP => 'CP_UTF8' );
    # or maybe
    # Win32::OLE->Options( CP => Win32::OLE::CP_UTF8 );
}
[download]