Simple. Just as you've added a filter to the_content, add the same function as a filter for templatedia_pre_template. The completed template will be parsed by your function right before it's inserted into the post/page's content.
This plugin has some very useful filters. Here are the two important ones:
templatedia_templates - modify the templates array to add new template(s). Note that the stub name needs to be lowercase. See the Templatedia Chess plugin for an example.
templatedia_variables - add to the list of variables that can be used in posts and templates. Do a global $post; if you need to. See templatedia-mediawiki-variables.php for an example.
There are also various other filters available for use, but which are highly technical in manner. You probably won't need to use them, but you can find out about them by reading the plugin's source.
Version 1.1.0
Version 1.0.0




