I'm using the registration add-on to simply register users. No other gravity form add-ons.
I made a registration form with Username, first, last, pass and a checkbox saying "check to agree to terms and conditions".
I made the checkbox required in the form editor.
I then went to the User Registration editor. Chose my registration form, mapped the fields and (this is the important part) set a registration condition. That said the terms and conditions checkbox "is" and pulled down the list to display "check to agree to terms and conditions"
The problem is that it just wouldn't register any users. I finally tracked it down to line 1548 in userregistration.php. It was always failing that and always just returning before getting to the user registration bits. I fought with this form for a couple hours before finally turning OFF the registration condition but leaving the checkbox as required in the base form and now everything works like it's supposed to.
As I'm writing this post I tried to re-enable the registration condition and actually can't get it turned back on like it was before. I can pull down the checkbox field but it won't populate the right hand dropdown after the "is".
Technically I don't need any assistance, this is more of a bug report. Or, if anyone else has a problem like I have, make sure you're very, very careful with what precisely you have set as registration conditions in the user registration portion of the form.