It seems I've opened a can of worms. I need a payment module for Accelerated Payment Technologies "XWeb" hosted payments.

Accelerated has provided tons of material including sample PHP code, documentation and specifications, though nothing specific for Zen Cart. I have no idea where to begin and frankly I'm a bit overwhelmed.

Is there a generic step by step tutorial that someone could recommend to at least get a start?

I'm no PHP expert and a noob with Zen Cart so the simpler the better!

Any help would be most deeply appreciated. Thank you.

*zen cart 1.39h php 5.3.4