My wife and I used to play FFXI together, we have an older daughter now who wants to play with us. We have three separate machines, but are all NAT-ed behind a router. We come in from one household IP.

Is this setup allowed?

I ask because we are trying to set up my daughters machine to run FFXI, and we didn't get the registration email.

If it's problematic is there anything we can do to play together, or do we need to share an account if we all want to play?

Thanks!

Who should I contact if a registration email didn't go through?

Did you check spam? Maybe try a different email address?