The default config settings for IMS Content Repository in mod/resource/type/ims/repository_config.php override any settings in config.php for the same variables.

We are a Moodle partner and with our hosting model, it's critical for us to be able to set these variables in the site-specific config.php rather than in the shared repository_config.php. This requirement may not be critical for everyone, but even so, the variables should be allowed to be set in config.php without being overridden.

I'm attaching a patch for repository_config.php that simply checks whether the config variables are already set before setting them. This allows the values to be set in either file depending on user needs.