Need some advice for good practices
 

So I am currently working on a PHP script which utilizes Smarty and I have written some code and pushed it to a github repo: amxbans

First I would like if someone takes a look and maybe give me some advices how to improve it, because although it's working fine, I have this feeling like "it's not the best way to do it".

Especially in parts like:

steamAvatar.php

if( !is_dir( 'avatar_c' ) )
mkdir( 'avatar_c' );
This two lines seem not to belong here, but I don't really know where to put them.

Thank you in advance.