In parallel with sorting the various connections I be inclined to look to replacing the upper tailgate seal which is likely to be the cause of all your problems.

Thanks for the info guys

Just found an old thread on here called "Fuses td6" which has all the same goings on as me from 3 years ago!
Remember posting on it nicedayforit?

^ You would think I would remember such a meaningful, helpful post but regrettably I don't.😇 Having said that most of the time now I can't remember what day it is. Fortunately these days I don't have to.

Hi all, me again!! Hahaa!! I have a update and its not good..... well I think i'm getting there!!!

I repaired the broken pin on the YIL000023 module by soldering a wire from inside the box to the correct wire on the loom and replaced everything - plugged the DSP amp that I'd bought the week before on the bay and nothing...

So I went round and checked fuse 49 which was blown!! At this point I was getting quite excited thinking that just a simple replacement fuse would solve all my car audio woes... After waiting for a while I replaced the fuse and turned the ignition...
Yay! I've got the screen back BUT with no options for radio, CD, or tape also no DSP on screen and no orange light next to the power button.
The nav is working tho?

After rechecking all the wiring looms for the modules are colour to colour in the boot I noticed the there seems to be some wiring missing from the BM54 harness? Pins 1,4,5 and 8? Do these need to be connected in some way? It looks like they where connected in some way before but there are no other bare wires on that loom?

I've circled them in the pics

Click image to enlarge

Click image to enlarge