Wordpress: Update plugins and customize 1 plugin

Hi, I need my Wordpress plugins to be updated without breaking functionality. When filling in or editing profiles and hitting save, it moves to the next group to fill in or edit. Profile fields that are not required and not saved by users do not show empty fields next to the profile picture when saving. The Buddypress plugins needs all additional code to be retrieved and placed in a folder in the child theme. I have a Preload & Pjax Faster Page Load plugin that needs to edited to not load in certain instances: It must not be loaded when logging in and out, hitting the signup button and facebook login button and the complete signup button on the register page. It also must not affect the profile div for user profiles. Also on profile edit, the text links above Editing Info, Details or About Profile Group must not show.