> I have one quick question. I am unclear 
> how Template and Template::Pro interact.
> For instance, If I use the following code:
> use HTML::Template;
> my $template = HTML::Template->( filename => $tmp_file );
> ..
> $emplate->output();
> With Template::Pro installed, will this code actually use Template::Pro 
> to parse and output the HTML? Or do I need to change the code to:
> use HTML::Template::Pro;
> my $template = HTML::Template::Pro->new( filename => $tmp_file )

use HTML::Template::Pro;
then, if you don't 'use HTML::Template;'
both are equivalent.
so call
my $template = HTML::Template->new( filename => $tmp_file )
also uses Pro.

It is better to develop code with HTML::Template,
because its debug facilities currently much better,
but to swich ready code to HTML::Template::Pro 
(replacing use HTML::Template with HTML::Template::Pro) 
because it faster, lighter and so on.  
On the other hand, it is useful for writing scripts which
works with both modules.

in case when both modules are loaded 
use HTML::Template::Pro;
use HTML::Template;

my $template = HTML::Template::Pro->new( filename => $tmp_file )
uses Pro,
my $template = HTML::Template->new( filename => $tmp_file )
uses HTML::Template.

> As I read the docs, the only reason to mix Template and Template::Pro
> would be that you needed query support from HTML::Template?

I also used mixing it in the same file for benchmark.pl.t

> I am considering using your html::template::pro and I have a question
> about the tmpl_include tag.  Is it possible to put a template variable 
> inside the file tag?
It is possible through EXPR="", for example, <tmpl_include expr="variable">.