The PKWARE PEM Administrator segregates Smartkeys by the Application they are registered for. This means that an Application will only receive the keys it is expecting and was designed for, not the keys created within the context of another app, which was potentially created by another team.
This is best explain by example. Consider two applications: the Smartcrypt Desktop product created by PKWARE, and a custom application written by your development team. Your application will typically fall into one of two buckets - either it wants to use the exact same keys as the Smartcrypt Desktop application is using, or it wants to use keys managed independently of what occurs in the Smartcrypt Desktop application. The SDK tab in the Manager is for the second case - your application wants to use keys different from those used by Smartcrypt Desktop.