> 1) a getTransactionSynchronizationRegistry() method on the TransactionManagerService
No problem, I can do that for the next release if you sill need it
> 2) a way to tell the TransactionManagerService not to bind that object.
This one I have a conceptual problem with. If a component needs the TSR it can currently ensure its presence by declaring a dependency on the TransactionService. That model will break if the TransactionService can be configured to provide only selected parts of its functionality. You would, IMO, need a separate TSR service that depends on the TransactionManager. Likewise for any other JNDI binding that may become optional. Or have I misunderstood the MC model?