You can use the following Variables :
$scriptname : Script Name
$path : Installation Path
$version : Version
$url : URL
$disable_notify_update : Update Notification
$auto_backup : Automated Backups
$auto_backup_rotation : Backup Rotation
$time : Time of Installation
$sn : Site Name (Can be changed from Webuzo Admin panel -> Settings)
$user_name : User Name
$user_email : User Email

Note : You can use an IF for an Optional Variable in the following manner :
<if $VARIABLE_NAME>$VARIABLE_NAME</if>