The CB IR is a full ICAO IR, and the skills test is same as the full IR skills test. Only the route used to obtain the IR differs. The CB-IR isn’t a rating, but more so a route to the rating. This is in sharp contrast to the normal commercial route to the IR via a modular or integrated course, where no prior experience is assumed.
The training requirements are reduced with 10 hours less flight training and 50% less theory, to make it more easy available for a larger number of pilots. The CB-IR does not include the HPA privileges. As already discussed, this can be done later. So if you do the ATPL theory and study for the IR via the CB-IR route. Your CB IR includes the HPA privileges.