Custom Mods for OpenCart

I'm using opencart and I've had multiple modifications that need fixing. I have a modification that determines commission for an affiliate when he uses a coupon. So, I enter a date, and a coupon with wildcard and it tells me how many orders have used that coupon and the total. It's not working correctly anymore and I can't get in touch with the old developer. I also have a bunch of other work, so do not bid on this project if you plan on disappearing in the next 5 years, we have lots of work needed to be done and a solid, dependable developer.