the error is saying that the permisions are not allowing folders to be crteated in the image_cache folder by the script.
In dreamweaver, set the files panel to Testing Server view, then right click the image_cache folder and select Set Permisions.
set the permissions to allow Read Write Access for the Owner , User / Group and Evewrybody users.
the second error is saying that the timezone is not set correctly in the PHP.ini file.
you need to set the date.timezone setting in the php.ini.
see the following for a list of excepted timezones: