Why aren't my base styles updating in the preview?
If you're removing styling from a base style, those styles still apply until you have saved the base style.
Acquia Cohesion renames to Site Studio from version 6.2. Tell me more.
You can only add combinators to child selectors. Add a child selector and combinator will appear in the Style tree.
Base styles are CSS styles for HTML elements.
HTML is escaped when using Drupal tokens in Site studio as a security measure, this follows Drupal core.
You don't. You apply a Descendant selector. These use a (Space).