Well with the Fantastico install, some of the functionality seemed a bit off, and eventually, I received some MYSQL errors which stopped messages going out. Thats with Bluehost anyhow, other hosts have Fantastico too so it might cause a disruption with PHPList integration. Which is why I mentioned it really, in case anybody has that setup and gets problems with this mod or PHPList in general.
But on our host, it is handled by Simple Scripts now and that works 100%. With the Newsletter Subscribe mod, I think that issue is there. I haven't really checked it out but I tested it briefly and it seemed ok. I have modded some checkout pages, so that scenario might happen as you mentioned.
With PHPList, I have an attribute setup for forenames. So a newsletter template setup correctly would start off, "Dear Joe...........". I guess that uses the same logic as the fields you mentioned, such as Gender and Email address. And making a call to the database fields to send to the PHPList database fields. From the original release of the Newsletter Center mod, I gather theres a lot of connecting to each database.
I saw that you have four areas, one of them the rewrite sidebox. I was just thinking, I don't know if you have to give the user TEXT and HTML options by law. Most sites I subscribe to just offer HTML. I thought HTML would suffice, but you might already have got it covered. Just based on my use of the Newsletter Subscribe - which has the two options in the sidebox.
Heathenmagic