If I change a Helper layout, will it change where it's used?
No. Helpers are coupled with the page once placed. Changes to the Helper layout will not affect existing instances.
Acquia Cohesion renames to Site Studio from version 6.2. Tell me more.
No, you cannot layout forms with Acquia Cohesion.
You can create more than one template to provide layout and style alternatives with the use of the template selector.
You can style tables or forms through the use of base or custom styles.
HTML is escaped when using Drupal tokens in Site studio as a security measure, this follows Drupal core.