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.
The style preview may not be updated because the refresh icon hasn't been toggled to the active state.
No site specific data is stored on the API.