Got it.
In 1.9.5 there is an option to auto-identify the top post below the first post which is what I thought you were referring to.
Let's start with the basics...
1. Be sure you enabled the option in your admin to use the variable.
2. Try using this code which will print out "FOUND IT" in the post:
Code:
<if condition="$thread[toppost] == $post[postid]">FOUND IT</if>