I did read it, but clearly my level of noob is blatantly obvious! This is starting to make a significant amount of sense. So as for in MAME, I simply have to make the controller a controller, rather than a keyboard? I need certain things explained like I'm stupid. Because I'm stupid.
In MAME, you should be able to highlight the control you want to change, hit enter, and then hit the button. MAME will pick up the next event (controller button, keystroke, etc) that gets hit. That board simulates a controller, not a keyboard, so you can't open Notepad or something and hit a key and see anything happen. You need to use something that shows controller buttons (joy.cpl does that).
It should just work, but if its not, use joy.cpl not MAME to see what is happening. It'll show you if a button is being registered or not.
One thing to be aware of, though -- Windows doesn't keep controller IDs stable, so if you plug/unplug any other controllers you'll likely wipe out the MAME settings and have to redo them. There's utilities that can help with it, but IMO controller interfaces are a giant pain in the ass.