The Send2CRM packages have a few Custom Settings. In Salesforce Setup, search for Custom Settings and note the following:

Essentials

Analytics

Organization-wide settings are automatically created with default values the first time the Send2CRM package is installed.

The Dashboard settings may be overridden per user by creating additional Custom Settings records. All other settings are always retrieved from the default/org-wide setting.

All other configuration is stored in custom mapping objects which can be managed by the Mapping Wizard.

The shared API key is encrypted and cannot be set directly via custom settings. An administrator may generate a new key on the Client Configuration tab of the Send2CRM app.

NEXT:

Permission Sets