We have some lovely new lights, one for each of two bathrooms but I've quailed before the morass of wires in this fitting. I've called in a professional. I had a go with a such fitting in our last house, one with more than three wires (Live, Neutral and Earth) and I had to ring our friendly electrician, who very kindly talked me through the connections on the phone, in his lunch hour. I took this photo to help with getting the new light connected, but there are too many wires for the new fitting and I don't have the necessary connection block ("Lego brick") to convert to the new fitting.
But this is the sensible course of action . . .