Documentation: All build instructions should mention caveats of not using berkeley db 5.3
Problem:
As experienced recently by @howelzy -- the berkeley db version one must build with should ideally be 5.3, otherwise if you built with something newer, and then you install the release version later after having run the app on your custom bdb-built version, the wallet.dat file (if you are using the internal bitcoind wallet) will not be readable on the release version.
This is a known issue with all Satoshi bitcoins, and not specific to ABC and/or BCHN. This has been a caveat of building your own bitcoind since time immemorial.
Solution:
All build instructions should mention this caveat. Apparently @howelzy was not aware of this caveat because the osx building instructions he read didn't mention it.