On the rear of the FF axles yo have two separate systems at work. Your main braking is the discs, which you see thru the wheels. If you pull your wheels and calipers you should see that the disc has an enlarged center section, or hat. If you pull the disc rotor off you will see what that diagram shows under that hat. Unlike a drum set up where the drum serves to both stop you and act as the e-brake, in this set up, you have a disc rotor that provides your main stopping for driving and then a separate drum setup inside that serves as your parking brake.
It is a good setup, but unless you pull your rear rotors regularly, and how many of us do that

, then the e-brake often gets overlooked.
I would guess that the "slop" that you were mentioning is a combination of the neglected parts and an e-brake that is probably way out of adjustment. I actually need to pull my wheels and do some more fine tuning to get mine to hold like it really should.
Good luck and if you have any specific questions, shoot me a pm, since I just finished this up I may have some other pictures, or will be glad to get you some if you need them.
Tucker