Not sure why you would prefer an unstable, unreleased hg trunk version to a stable, released one.

And as you've seen, Python 2 and Python 3 are quite different things.

As for dl failing on build, you've already stated that it does *not* build, together with bsddb185 and gdbm (for which the library headers are missing).  setup.py does exactly that test for 64-bit platforms.  Then you activate it explicitly, and complain that it does build...

And lastly, all these things are *not* a build failure of Python: missing modules just means that, well, these modules won't be there.  And failing tests just means that there *may* be a problem when using the respective module -- but for platform-dependent modules it could just as well mean that your system is configured in a special way.