paypal URLs question

Any chance of getting some help with the parameters required by PayPal?
I have been reading FAQs, docs and searching forums both on here & on PayPal for 4 days now and it seems like the most obvious information is nowhere to be found! Specifically:

• Cancel URL - I am using "https://www.mysite.com/members/cart/index.php?main_page=shopping_cart"
• Error URL - Is this a page I have to write to capture parms returned & if so, how do i get Zen Cart to recognize it exists? I tried putting it into /includes/extra_datafiles/ and that SO didn't work!
• Return URL - Using "https://www.mysite.com/members/cart/index.php?main_page=checkout_success"
• Security Token - How to enable this in Zen-Cart? I have entered my "API Signature" info, but wonder if **that is compatible with my PayPal Manager (PayPal Payments Advanced) account. I have successfully enabled "Payment Data Transfer" on PayPal and have an "Identity Token" but am at a loss as to how to enable or even get a Security Token.

I am running Zen Cart v1.5.1 on an Apache Server (DreamHost) using PHP Version 5.3.13 & mySQL Client API version 5.1.66

Thanks in advance!

Donar:

Any chance of getting some help with the parameters required by PayPal?
I have been reading FAQs, docs and searching forums both on here & on PayPal for 4 days now and it seems like the most obvious information is nowhere to be found!Probably because all the URLs for PayPal are already built-in to the PayPal modules, and there's no need to change them!

Why are you wanting to change them?

DrByte:

Probably because all the URLs for PayPal are already built-in to the PayPal modules, and there's no need to change them!

Why are you wanting to change them?

Nevermind, it was a fool's errand. I was trying to jury-rig ZenCart to work with PayPal Payments Advanced (PayPal Manager) in spite of not having a pre-packaged module for it. The alternative is to use PayPal Payments Pro but I didn't want the responsibility of managing my customers' CC info. But that seems to be the only option for now, so I will just upgrade my Payments Advanced acount to Payments Pro so I can get the site up & running while I tinker in a "sandbox" to try & bugger it to work with Payments Advanced.

Sorry to have wasted your time, both with a silly question and with posting it into the wrong thread.