How to apply the Contrib theme to a Drupal-6 site without changing the administration theme - theme tab for the site and Garland for the administration interface -?
Thanks.
Go to "Administration" → "Site Configuration" → "Administration". There you can install the administration theme. If you need additional control over the administration topic, use the Admin Theme module.
For an administrator (with UID 1), go to his user profile (in / user / edit / 1) and change the theme, but set the default theme (in / admin / build / themes) to the desired theme.