Contributor roles

I am trying to set a custom role for Contributor and can’t seem to prevent it from publishing to the live site. Basically I need my contributors to do editing including uploading files, but the only thing they aren’t allowed to do is PUBLISH. I’ve tried a number of things and can’t seem to prevent my test account from publishing changes. Please let me know what I’m doing wrong.

https://wordpress.org/plugins/user-role-editor/