Other PHP based web scripts. Generally add-ons for GPL licenced software.
Module for WHMCS to publish Automatic Backlinks links
Install as any other WHMCS modules, by unacking the zip file you download, and upload its contents to WHMCS's /modules/addons/ folder.
Edit the automatic-backlinks.php file, and replace this line:
$abAccountCode = "2890d2069034d55175b443f468042d64";
to contain your personal Automatic Backlinks code.
Activate it in WHMCS backend in the Setup>Addon Modules page.