plugin gone awry?

[lukemax]

Is there a way to check a plugin to see if its working? In a hook I trying to get to work, I have this

PHP Code:

ob_start();
   include('../reviewform_hook.php');
   $reviewform = ob_get_contents();
ob_end_clean(); 


I can get to the included file via the browser, but when I try to use the variable

PHP Code:

$reviewform 


in a template, I get nothing?
What is wrong?