CSP||B is an approach to combining the process algebra CSP with the formal development method B, enabling the formal description of systems involving both event-oriented and state-oriented aspects of behaviour.  The approach provides architectures which enable the application of CSP verification tools and B verification tools to the appropriate parts of the overall description.  Previous work has considered how large descriptions can be verified using coarse grained component parts.  This talk considers a generalisation of that work so that CSP||B descriptions can be decomposed into finer grained components, _chunks_, which focus on demonstrating the absence of particular divergent behaviour separately.