I do this all the time using a little snippet I got from Susan Ottwell (MODx user sottwell). I do not remember where she said she got it. Maybe it is from Etomite. Anyway, Here is the snippet. I have it saved in my manager as "Template".
<?php
if ( !isset($template_file) || $template_file == "" ) return "No file specified."; //check if there's a file given.
ob_start();//Start the buffer
include $template_file; //include
$ob_contents = ob_get_contents();//get contents from the buffer
ob_end_clean();//and kill/delete the buffer
return $ob_contents;//return it to MODx.
?>
Now, if I have my template files (CSS, images, and template.html) stored in /assets/templates/mytemplate/, under the Manage Resources->Templates tab, in the area where you would normally put the template code, I put this instead.
[[Template? &template_file=`assets/templates/mytemplate/template.html`]]
You would of course replace "mytemplate" with the name of the folder your template is in and "template.html" with the name of your template file.
Now it is easy to edit the template because each time you update that file in dreamweaver and sync it with the server MODx reloads it’s contents from that file rather than from what is stored in the database. This probably adds some extra overhead, but makes it easy for modifying, refreshing, and checking the layout. Once you have it looking good, then it is a good idea to put the template code directly in the database, but this works great for tweaking your template code!
-sD-
Dr. Scotty Delicious, Scientist