BrowseForFolder() doesn't (yet) support this style of calling. And there aparently was a bug in the code. Could you try to replace the BrowseForFolder in FileOp.pm with the following code:

sub BrowseForFolder {
   undef $Win32::FileOp::Error;
   my $lpszTitle = shift() || "\0";
   my $nFolder = shift() || 0;
   my $ulFlags= (shift() || 0) | 0x0000;
   my $hwndOwner = (defined $_[0] ? shift() : GetWindowHandle());

   my ($pidlRoot, $pszDisplayName, $lpfn, $lParam, $iImage, $pszPath)
      = ("\0"x260, "\0"x260, 0, 0, 0, "\0"x260 );

   $nFolder = CSIDL_DRIVES() unless defined $nFolder;

   $Win32::FileOp::SHGetSpecialFolderLocation->Call($hwndOwner, $nFold
+er, $pidlRoot)
   and return undef;

   $pidlRoot = hex unpack 'H*',(join'', reverse split//, $pidlRoot);

   my $browseinfo = pack 'LLppILLI',
      ($hwndOwner, $pidlRoot, $pszDisplayName, $lpszTitle,
       $ulFlags, $lpfn, $lParam, $iImage);

   my $bool = $Win32::FileOp::SHGetPathFromIDList->Call(
               $Win32::FileOp::SHBrowseForFolder->Call($browseinfo),
               $pszPath
              );

   $pszPath =~ s/\0.*$//s;
   $bool ? $pszPath : undef;
}
[download]

and then use

my $dir1 = BrowseForFolder("with handle", undef, undef, $windowid);
[download]

I have a few more changes pending to be released, hopefully I'll have some spare time to do that sometime soon.