Do I have to use IMCE?
No. Acquia Cohesion allows the site builder to select, either use of IMCE or Entity browser for browsing and selecting images.
Acquia Cohesion renames to Site Studio from version 6.2. Tell me more.
Google maps may not be showing if you have not set a Google maps API key.
HTML is escaped when using Drupal tokens in Site studio as a security measure, this follows Drupal core.
Yes, this is possible by creating a custom element.