Shopping Cart Edits - DigiVendor Pro

I had someone else from this website make some edits to the shopping cart by adding a free download option to the cart. When the software was untouched, someone would order a product (digital download) and then be emailed a username and password to download their products. I need the password to be changed. It's a random generated password similar to this: -5773629940 I need this password to not have the "-" and be a combo of letter and numbers. In the backend there is a button that says "Manage Customers". When someone has bought an item that has a price (anything more than free) they get added to this list. Here is a sample listing: [login to view URL] Username: admin Password: admin I need to make sure that all of this information from both forms (the free form, and the paid form) is being inserted into the database for us to review. Also something to be noted is that once a customer becomes a customer of the store, when they purchase something, there should only be ONE listing for the customer. This means, if they buy more than one item, they shouldn't be inserted into the Customer list more than once. They can buy multiple products with one account. [login to view URL];uid=6 On the right side of the page there is a "Mailing List" button. Currently this does not work in my shopping cart. What is should do as you can see in the demo here: [login to view URL] is... list out, seperated by line break, each customers email address so we can copy and paste their email into our newsletter database. Also right now you cannot add more than one item to the shopping cart. We would like to add this feature. The reason it exists now the way it does is because the free products use a different form than the paid products do to order. But we got to thinking... What is the customer wants to buy the eBook, and get the Free Download? Why should they have to do two transactions? I will have a ton more work for whomever can do it right. Here is our online store: [login to view URL]