Upgraded from 4.1.15 to 4.6.10 with no errors, setup file system ownership & permissions, cleared template_c cache, ran drush cvapi system.flush Working but layouts are wrong and the log file contains errors with "User warning: Smarty error: unable to read resource : "CRM/common/action.tpl" in trigger_error() (line 1094 of ../sites/all/modules/civicrm/packages/Smarty/Smarty.class.php).
Directory modules/civicrm/CRM does not contain a common directory.