The optional Loading Object is of type SoftwareLoadingType, which is abstract. The Object can be one of the concrete sub-types DirectLoadingType (8.4.4), CachedLoadingType (8.4.5) or FileSystemLoadingType (8.4.6). SoftwareLoadingType is formally defined in 8.4.2.
The Loading Object is required for all variations of software installation, it is not required for read or restore of device parameters using the Parameters Object.