fixerdave wrote: So, to finally get around to what this post is about, can anyone recommend an approach to learning how phpBB all fits together? I'm just looking for some cracks and toe-holds I can use to start scaling the learning curve. I don't need the "how to use or install" info, I want hints on making mods, understanding the code, that kind of stuff. What's out there?
I don't think this is something you didn't know yet, but you learn best by just trying. Back in the days when I wasn't even capable of writing a simple "<?php die('hello world'); ?>", I insisted on getting this complicated, weird piece of software called phpBB to do what I want. So, I started hacking around and after many, many hours of googling around and countless visits to php.net, I am where I am now
There really is no best approach, and neither are there best practices for getting a feeling of the phpBB internals. Set yourself a goal, do whatever it takes to reach that goal, and move on to the next challenge.