New Zope Python-Level Debugging HowTo

I've been accumulating some tips and tricks for python-level debugging in Zope - mostly clues about Zope mechanisms that may not be as well known as they could be. Been sitting on it too long waiting for time to polish it, but that ain't happening, so i took less time to partly polish, and here 'tis. I'd be like to hear about missing things that ought to be included here, as well as corrections to what is...