IDev affiliate track free trial to recurring

Hi, we are hoping to integrate IDev affiliate into our site as many others have done successfully, using the s2member plugin. Unfortunately, the info I find suggests there may be a problem, and I am sure there is in fact an answer but I can’t turn it up.
We offer a free 7 day trial on our signup page, after which a monthly subscription starts for 24.95.
But just as s2member won’t let you set a price under .01, IDev won’t let you put in 0.00 for the price in their code, which suggests that you cannot do a trial, and have to hardcode in a price. You can enter “recurring” but it doesn’t kick in a number for seven days.
While we want to pay affiliates recurring on the 24.95 subscription if people sign up, we don’t want to pay that rate if someone stops after 7 free days.
So we can’t just hardcode in the correct price — usual solution — since that would pay out the affiliate on 24.95 even if they cancelled, right?
And we can’t put a lesser amount in (penny, dime – a cost but reasonable for the effort) because then the recurring payment amount would be incorrect for people who subscribed.
Unless s2member just holds onto the tracking pixel until an actual billing event occurs. Which would be great and even make sense, but it isn’t documented like that anywhere I have found. We can’t be the first to confront this and are hoping you have a recommnded setup or workaround that doesn’t involve abandoning our free trial.
IDev said this: As far as the free-trial stuff you’d want to talk to S2 to see how they handle the iDevAffiliate integration. […] You will indeed get a “Processing Error” if the sale amount passed into iDevAffiliate is 0.00 OR if the commission amount is less than 1 penny. The question for S2 though is whether or not they still call the tracking pixel with a 0.00 sale amount (free trial for instance). What I think will happen is the tracking pixel isn’t called immediately for the free-trial and will only be called if the sale amount is positive which means 30 days later (or whenever the customer is charged), the pixel will be called and the affiliate will start getting commissions from that point forward.
So what’s the answer and I hope I have enough keywords future users can find this post if they confront the same issue.

This is easy Nate.

You want to be using the CURL of your installation in conjunction with the ‘payment notification’ API.

Don’t use any of the options in the API >Tracking menus, use the API > Notification menu and fill in the payment notification with a dynamic cURL.

You will get your cURL tracking pixel from our idev dashboard under settings > API > Advanced or similar I think.

I’m on my iPhone so can’t check just now, but it’s the bottom of the first drop down from the left in the admin screen.

Paste this URL into the payments notification setting and then replace the amount, order number etc with the replacement codes S2 list on that page.

This way you will ONLY pay commission when you GET PAID, not when someone signs up, so trials are totally possible.

Hope that helps!

Thank you so much!
the cUrl is where you said, but for the record exactly:
Setup & Tools> Advanced Developer Tools> Custom Functions

I will be testing
http://oururl/sale.php?idev_saleamt=%%amount%%&idev_ordernum=%%payer_email%%&ip_address=%%user_ip%%

(all on one line is S2member of course)

We shall see what happens as things recur….

Looks good to me Nate!

Now that will cover you for ALL payments except for those associated with specific post/ page purchases.

If you use those, create a new link under the post/ page notification on the same screen API > Notifications.

You should have all bases covered at that point. :)