new user registration failing - need ZC expert help please

Dear Group,

I have a store-bought template that I have extensively modified. I have also installed the "Fast Easy Checkout" mod.

Everything is working fine, except for one thing - it is no longer possible for my users to create an account in my shop! They fill-in the form, submit it, and it sends them back to the same form again.

I know that I have heavily modified the site - I'm a relatively competent programmer, so you can speak to me "technically" - but I am completely lost as to why my site is failing! It is sending exactly the same information (including hidden fields) to exactly the same Zen Cart subroutine... but somehow not only are the customers being sent back to the registration page, but their registration is failing! (doesn't show-up in the Admin Customers page)

To see what I mean, please visit http://getsculpt.com/shop/index.php?main_page=login and attempt to create a customer profile.

I have several profiles that I created before my mods, and I am able to login using those profiles, so that isn't the problem... the problem is limited to creating new profiles.

Any ideas? Anyone? I'm at a total loss!

Thanks to all who try :-)

Mark

I have several profiles that I created before my mods
Either back out the mods or create another install and add them one at a time checking the functionality after each

Ugh... I'd rather not do that... it's my live site, and the mods are important for customer retention.

given that MOST customers do not want to create an account, I can survive without this functionality for a while, but what I really want is for someone who knows the Zen Cart code fairly intimately to suggest what I might have screwed-up. Either with my own mods, or with the FastEasyCheckout mods (which I had to hand-manipulate before installation so that they wouldn't conflict with my own mods!) or...???

I'm sure there's a simple explanation, but it isn't obvious to me...

Thanks, though!!!

I'd rather not do that... it's my live site
create another install and add them one at a time checking the functionality after each

Thanks for the ideas, but...

I'm still hoping for suggestions that might help me understand the workings of Zen Cart itself, rather than just a trial-and-error approach.

Can anyone suggest what kinds of mistakes might lead to the code to behave the way it is? I haven't changed any of the core code, only the php templates that result in the HTML pages (though I suspect COWA changed some core code...)

Can anyone suggest what kinds of mistakes might lead to the code to behave the way it is?
When dealing with contributed non standard 3rd party code T&E is the method - - Unless you find another that has exactly the same compliment of addons that you have
A list which you have not provided BTW

For future reference, always backup before adding any module and then test - test - test before moving on