You're not the first to think this so DON'T PANIC (please), hopefully things will get clearer as you get more into it.
As mentioned on the Trackers doc page tikitrackers.org gives a pretty good high level overview of the feature - it started out as the Tiki bug tracker (and still is here) but over the years (and decades) it has grown into a bit of a monster!
This is why Tiki Profiles exist, which you can think of as macros - scripts that set up complicated features for a tiki in one click. So if you have a spare Tiki (not in production) you can try out the profile i mentioned before and that should end up with some instructions on how to use it. If not you can use http://demo.tiki.org/21x (i think it gets reset every Sunday night)
Gottago, hope we can help you through this!
P.S. We're always looking for people to help with the documentation, especially with the perspective of fresh eyes, so please do improve anything you think needs it as you go along if you can, thanks!