Newbie Plz Help - Added to DB can't get rest to work

Greetings,

I know many people hate questions from, and get perturbed by "newbies", so please forgive me.

I am using ZC 1.39c that is one of the carts offered with the web hosting company my friend is using. I finally have the site working, but an additional piece of customer information is needed. I successfully added "customers_drivers_license" to the DB; however, I've been unsuccessful at getting it added into the various PHP files. I followed the example of one person in the forum; however, when I chose to add an item to the cart as a new customer, the page was blank. I'm sure I screwed something up.

I would really appreciate any help with exactly what I need to input, where in the respective PHP files, and which PHP files I need to update. I have to make the online store active on June 6th.

Thank you very much!

Rod