Not creating signups after payment entered (either for checks or paypal). Relevant Session Variables and Database Tables empty.

For one product class, it seems to work just fine. For the later one we created, which has no real difference, it doesn't.

I check the database through the order process, and the signup never gets put in the uc_signup table. Never. So I guess they can never transfer over, since they don't exist.

The setup is pretty basic for me. No multiple signups are allowed. Only the person can sign up themselves.

No sure if it's related, but I get after every order completion with a signup, the error:

warning: Invalid argument supplied for foreach() in /sites/all/modules/uc_signup/uc_signup.module on line 1012.

Which is:

foreach ($_SESSION['uc_signup']['nids'] as $nid => $attendees) {

But I've checked, and that Session variable is always, indeed, empty at that point.

Any clues? People are paying, but not getting recorded.

Thanks.