RNS-D to RNS-E Retrofit - Couple of Questions

[steamship]

Toying with the idea of fitting a RNS-E, and looking a few answers. I've read through the following two threads a couple of times, created by IT and Singh back in 2010, but I seem to be missing some references to various bits. Hoping that someone has a very good memory of doing these.

IT's thread: http://forum.a8parts.co.uk/showthread.php?t=1544

Singh's thread: http://forum.a8parts.co.uk/showthread.php?t=1600

I've also borrowed some of their photos for reference to explain what I mean.

1. RNS-E - Ian showed a picture of the back of the RNS-D and RNS-E and said that none of the connectors were transferable. Looking at the photos of the various Kufatec items Ian also posted, there is a large multi-pin connector on the RNS-E that I didn't see anything being connected to. All the other connectors I can figure out. What is this connector (#1 in the first picture) for as it seems pretty prominent? Singh shows a picture of the back of his RNS-E and that connector doesn't have anything fitted.

2. RNS-D - Singh showed a picture of a bunch of cables that he couldn't find a destination for. The two of those I'm interested in are the large black rectangular connector and the round black multi-pin connector. If none of the connectors are transferable, does that mean this black one is redundant? The round black connector I know comes from the CD changer (and plugs into #2 in the first picture), but again it doesn't seem to connect to the RNS-E, so how does the RNS-E control the CD changer?

Can't get my head round the fact that two seemingly important connectors on the RNS-D can be made redundant, with the only loss of features being the navigation display in the DIS.