Rob, do you have an updated or more concise demonstration of the issue... specifically one that is compliant with local-context fall-through deprecation?
Unfortunately the current state is not yet stabilized enough and quite a few changes have occurred since the last report that I'm currently unable to provide what you request. However, I have already fixed the context-fall-through issue and will be revisiting the local macro variable issue again soon - testing against Nasm v2.10rc's - so look to hear back from me