Can we actually make a list of what's wrong? It's kinda tricky because some of the errors have mistakes in them. It's non-compliant in so many ways, perhaps more interesting is to work out where the real danger lies.
If I'm reading Marcus's comments right, it's fed from a 15A BS3036. On paper the cable is not rated for that (nor for 'power' circuits of any rating) but in truth it would be very hard to overheat it badly on a 15A fuse unless it's fully embedded in thermal insulation. Seems the fuse hasn't blown, so although the Ib, Iz and In are all the wrong way about, it's probably not going to hurt anyone.
The MCB rating is irrelevant - if the incoming cable isn't going to melt, the outgoing ones won't either. There are lots of legacy circuits without RCD protection; not connecting it doesn't make it any more dangerous than those. The colour code doesn't make any difference until you start modifying or testing. The leccy doesn't care which wire is which. Grommets, bare copper, chock block, meh.
Which brings us to that earth bar, sorry, neutral bar. The one used for the neutrals because the lines are in the proper neutral bar. It's connected to the case, although the outgoing earths are connected to earth, it seems. This gets my vote as the main risk here - one loose connection and that casing goes live. (TN-C is also prohibited, FWIW).
Thankfully that is easy to solve - take the link out, job's a good'un!