[calorie]

In the vB PHP files you will find constants:

// in the index.php file near the top
define('THIS_SCRIPT', 'index');

// in the showthread.php file near the top
define('THIS_SCRIPT', 'showthread');

Use THIS_SCRIPT in template conditionals:

<if condition="THIS_SCRIPT == 'index'">
	on forum index page
<else />
	not on forum index page
</if>

<if condition="THIS_SCRIPT == 'showthread'">
	on forum showthread page
<else />
	not on forum showthread page
</if>