I used this write-up to add the integration betweek GF to membership: https://premium.wpmudev.org/forums/topic/gravity-forms-and-membership-signup#post-232538. I've added the code to the theme's function.php. I also created this write-up to help the setup:
1. Create a Gravity From and set it up for User Registration.
2. In the Form Settings set the "Confirmation" to redirect to the appropriate membership registration page. This is redirected to http://ynpn.org/chapter/membership-payment-page/. This can be changed of course to whatever you do, just wanted to make the link. The member subscriptions are controlled here: http://ynpn.org/chapter/wp-admin/admin.php?page=membershipsubs&msg=3. This is done after creating the Access Levels here: http://ynpn.org/chapter/wp-admin/admin.php?page=membershiplevels. The Free is for the public, please confirm that all pages and posts you want to be public are there and check off the onces you do want for the public. That way when you enable the membership option it won't lock up for the public.
3. Embed the GF User Registration form in any page that is NOT a page setup in your Membership Options.
-- This is important and cannot be any page within the Membership Admin Options. Link the user registration form here: http://ynpn.org/chapter/wp-admin/admin.php?page=gf_user_registration. You'll need to activate the payment gateways you want to use here: http://ynpn.org/chapter/wp-admin/admin.php?page=membershipgateways. If free, make changes in subscriptions and activate that option under payment gateways.
Once this is complete, we should try run through the whole process from registration through the end, maybe create a test member account that can be used for this. I actually feel like this is getting us to a place where we can be much more flexible and do more based on each chapters needs, so I really appreciate you emails and help with this. Let me know if this all makes sense.
However, I am having issues here: http://ynpn.org/phoenix/membership-application/, this should redirect to http://ynpn.org/phoenix/register/ but it doesn't. The email gets send to the new member and even when they click on the login link from email, it just takes me to homepage. Any thoughts on what I may have missed?