New login from membership plugin

Hello
I am working o a directory page with gd and I am very impressed about all its features. But sometimes I get lost and need help:

If a not logged in user wants to add a new posting he is directed to the standard register/login-Form (see picture 1).
I have a membership-plugin running because I have some pages I want to hide to not logged in members. It is called Simple WordPress Membership and it syncronizes members with wp-member and with my mailchimp-list.

Problem: Now I have two register- and login-forms. And from gd-login it does not synchronize with the membership-plugin and mailchimp.

What I want is the following:
If a not logged in user clicks on „add a Profile“ (https://meine-agentur24.com/add-listing/?listing_type=gd_freelancer or https://meine-agentur24.com/add-listing/?listing_type=gd_projekte) he should be directed to https://meine-agentur24.com/membership-login/ instead oft he standard gd-form.
How can I archive this?
Thank you very much for your help!
Ulf