Concerning plugin changes and/or white listing

I read on your site that I can change the plugins and/or white label for my clients as long as I never sell the plugins. Please verify that I am allowed to change the plugin name, URL, author that is currently pointing to wpmudev. Or advise what part I am allowed to change to in the actual plugins as I do not want to violate any regulations. I want my clients to come to me if they have questions. Thanks