Warning: HTML is not XML ... unless you are dealing with XHTML ...
HTML::TreeBuilder might not work because of your non-HTML tags (the <TMPL_IF> tag), so if the document is "well formed" then I would use XML::Twig: 
use strict;
use warnings;
use XML::Twig;

my $twig = XML::Twig->new(
    pretty_print  => 'indented',
    twig_handlers => {
        TMPL_IF => sub {
            my ($t, $TMPL_IF) = @_;
            $TMPL_IF->set_text( 'changed it' );
        }
    }
);

$twig->parse(\*DATA);

$twig->print;

__DATA__
<html>
  <head> <title> test </title> </head>
  <body bgcolor='red' >

    <errors>
      <TMPL_IF NAME='INVALID_WIDGET_SIZE' > waka waka </TMPL_IF>
      <TMPL_IF NAME='INVALID_WIDGET_COLOR' > waka waka waka </TMPL_IF>
    </errors>

    <table>
      <tr colspan='2'>
        <td> text </td>
        <td> text2 </td>
      </tr>
    </table>

  </body>
</html>

[download]
output: 
<html>
  <head>
    <title> test </title>
  </head>
  <body bgcolor="red">
    <errors>
      <TMPL_IF NAME="INVALID_WIDGET_SIZE">changed it</TMPL_IF>
      <TMPL_IF NAME="INVALID_WIDGET_COLOR">changed it</TMPL_IF>
    </errors>
    <table>
      <tr colspan="2">
        <td> text </td>
        <td> text2 </td>
      </tr>
    </table>
  </body>
</html>

[download]
Here, XML::Twig is simply used as a filter, but once your XML is parsed in the $twig object, you can easily access the elements and change their content/tag/attributes.

In reply to Re: XML::Simple problem, or How to convert HTML to Perl and then back again. by choocroot
in thread XML::Simple problem, or How to convert HTML to Perl and then back again. by Wonko the sane

Title:
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