This small mod is going to make so much difference to our site. It installed first time no problem, runs well and suits all our needs. We can load our site with members by going to large groups on FB and other networks with similar interests and issuing or "leaking" a "Free" Premium memership voucher code. When we have recruited enough like this we can stop the offer and wait for them to invite their friends who will need to pay to upgrade. On public holidays we can offer 50% see more discounts to entice FREE members to convert to Paying members. This tool is going to be invaluable to us.
Great job and a great product.