Here's the basics that you really need to know.
In changer mode, pressing the button on the underside of the steering wheel remote should select the next disc in sequence, or pressing numbers 1-6 on the stereo front panel should select the appropriate disc directly.
The top button(s) on the remote cycle between AM/FM/head unit CD/CD changer. The wheel on the back of the remote lets you skip tracks on CD or flick between preset radio stations. Buttons on the end of the remote are volume up and down (pull them towards you.) Pull both simultaneously to pause/mute the stereo, and again to resume.
On a long CD track, you can 'rewind' and 'fast forward' through a song by pressing and holding the previous/next track buttons on the front of the radio. You can't do this from the remote.
The player handles most brands of CD-R perfectly well, so make copies of your albums and you won't be out of pocket if someone decides to steal them. Spare magazines pop up on
cheaply enough if you want one - it means you can pre-load the spare and just swap out the magazine next time you go out to the car.