Don't have pics, but when the nav is playing a CD or playing the radio, all there is is the track # or station frequency in the upper-left-hand corner of the screen. No, the text of a track name isn't displayed, but the name of the station is if it uses RDS (not sure how it works in UK).
No, there are no preamp outputs from any BMW headunits -- you have to tap into the factory harness in the trunk and convert the signal for most amps, or buy a high-end amp that accept balanced differential inputs.
A cd changer can most definitely be hooked up to a nav-equipped car and BMW would like you to buy one of their very expensive OEM ones. If you shop around, you should be able to find a decent price on the Alpine-made BMW changer. Not sure how good the deals are on the compact sized Nakamichi-made changer that fits in your glove box.
Otherwise, you can buy a Sony, Alpine or Pioneer changer and hook it up to the factory system if you buy an adapter from Peripheral or Soundgate. Search the ICE threads and you'll get more info.
Better picture coming!