It would be really great to have the invitation code checker working - without it I am having to look around for another solution -
I'm trying to achieve...
A private network (just the home page visible to non-members.) - registration disabled.
Members can invite people - meaning that they can send an invitation and in so doing generate a code that will give access to the private network.
Invited person accepts invitation which gives access enabling them to set up a profile and participate.