One thing that can cause confusion, is that invariably, as shown in the diagram in post #2 above, twin cable (usually with the bare earth wire) is used from the ceiling rose to the switch, though the black (or blue) wire is not a neutral wire - it's the switched live, and it's that black wire (or on modern wiring blue), which is the live to the lightbulb holder. In a standard ceiling rose as shown in the diagram in the central 'loop' terminal block you have the loop in from the consumer unit, the loop out to the next ceiling rose on the circuit, and the live down to the wall switch. To save confusion, there should be a piece of brown (or red on obsolete wiring) sleeving at each end of the switched live as shown in the diagram below, but as often as not, there isn't.
Hope that might help.